<?xml version="1.0" encoding="US-ASCII"?>
<!-- RR Donnelley Xcelerate Taxonomy Labels Linkbase, based on XBRL 2.1  http://www.rrdonnelley.com/ -->
<!-- Version: 6.22.4 -->
<!-- Round: 5 -->
<!-- Creation date: 2015-03-30T17:40:38Z -->
<!-- Copyright (c) 2005-2013 R.R. Donnelley & Sons Company All Rights Reserved. -->
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccruedLiabilitiesAndOtherLiabilities_lbl" xml:lang="en-US" id="id_7047976_1282048_1_1">Accrued Liabilities and Other Liabilities</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_AccruedOverPaymentsAndRefunds" xlink:label="cdna_AccruedOverPaymentsAndRefunds"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_AccruedOverPaymentsAndRefunds_lbl" xml:lang="en-US" id="id_7047976_1574563_3_1">Accrued Over payments And Refunds</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_AccruedOverPaymentsAndRefunds_lbl" xml:lang="en-US" id="id_7047976_1574563_1_1">Accrued Over payments And Refunds</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_AccruedOverPaymentsAndRefunds_lbl" xml:lang="en-US" id="id_7047976_1574563_2_1">Accrued overpayments and refunds</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AccruedProfessionalFeesCurrent" xlink:label="us-gaap_AccruedProfessionalFeesCurrent"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_AllomapMember_lbl" xml:lang="en-US" id="id_7047976_1577569_3_1">Allomap [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_AllomapMember_lbl" xml:lang="en-US" id="id_7047976_1577569_1_1">Allomap [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_AllomapMember_lbl" xml:lang="en-US" id="id_7047976_1577569_2_1">AlloMap [Member]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="dei_AmendmentFlag"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AmendmentFlag_lbl" xml:lang="en-US" id="id_7047976_1276506_1_1">Amendment Flag</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_AmendmentMember" xlink:label="cdna_AmendmentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_AmendmentMember_lbl" xml:lang="en-US" id="id_7047976_1387214_3_1">Amendment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_AmendmentMember_lbl" xml:lang="en-US" id="id_7047976_1387214_1_1">Amendment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_AmendmentMember_lbl" xml:lang="en-US" id="id_7047976_1387214_2_1">Amendment [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_AmendmentMember" xlink:to="cdna_AmendmentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_AmortizationOfDebtDiscount" xlink:label="cdna_AmortizationOfDebtDiscount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_AmortizationOfDebtDiscount_lbl" xml:lang="en-US" id="id_7047976_1489755_3_1">Amortization Of Debt Discount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_AmortizationOfDebtDiscount_lbl" xml:lang="en-US" id="id_7047976_1489755_1_1">Amortization Of Debt Discount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_AmortizationOfDebtDiscount_lbl" xml:lang="en-US" id="id_7047976_1489755_2_1">Amortization of debt discount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_AmortizationOfDebtDiscount" xlink:to="cdna_AmortizationOfDebtDiscount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium_lbl" xml:lang="en-US" id="id_7047976_1287300_1_1">Amortization of Debt Discount (Premium)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium_lbl" xml:lang="en-US" id="id_7047976_1287300_2_1">Amortization of debt discount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AmortizationOfDebtDiscountPremium" xlink:to="us-gaap_AmortizationOfDebtDiscountPremium_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AmortizationOfDeferredLeasingFees" xlink:label="us-gaap_AmortizationOfDeferredLeasingFees"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AmortizationOfDeferredLeasingFees_lbl" xml:lang="en-US" id="id_7047976_1287301_1_1">Amortization of Deferred Leasing Fees</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AmortizationOfDeferredLeasingFees_lbl" xml:lang="en-US" id="id_7047976_1287301_2_1">Amortization of upfront license fee</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AmortizationOfDeferredLeasingFees" xlink:to="us-gaap_AmortizationOfDeferredLeasingFees_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_AmortizationOfDeferredRevenue" xlink:label="cdna_AmortizationOfDeferredRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_AmortizationOfDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1297318_3_1">The amount of amortization of deferred revenue during the period.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_AmortizationOfDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1297318_1_1">Amortization Of Deferred Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="cdna_AmortizationOfDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1297318_14_1">Amortization of deferred revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_AmortizationOfDeferredRevenue" xlink:to="cdna_AmortizationOfDeferredRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xml:lang="en-US" id="id_7047976_1285739_1_1">Amortization of Financing Costs</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xml:lang="en-US" id="id_7047976_1285739_2_1">Amortization expense</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AmortizationOfFinancingCosts" xlink:to="us-gaap_AmortizationOfFinancingCosts_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xml:lang="en-US" id="id_7047976_1285740_1_1">Amortization of Financing Costs and Discounts</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl" xml:lang="en-US" id="id_7047976_1285740_2_1">Amortization of debt discount and noncash interest expense</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:to="us-gaap_AmortizationOfFinancingCostsAndDiscounts_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xml:lang="en-US" id="id_7047976_1280165_1_1">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xml:lang="en-US" id="id_7047976_1280165_2_1">Potential dilutive securities excluded from diluted net income (loss) per share attributable to common stockholders, Total</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xml:lang="en-US" id="id_7047976_1268687_1_1">Antidilutive Securities [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xml:lang="en-US" id="id_7047976_1268687_2_1">Antidilutive Securities [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xml:lang="en-US" id="id_7047976_1278584_1_1">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xml:lang="en-US" id="id_7047976_1278584_2_1">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xml:lang="en-US" id="id_7047976_1268688_1_1">Antidilutive Securities, Name [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xml:lang="en-US" id="id_7047976_1268688_2_1">Antidilutive Securities, Name [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="us-gaap_AntidilutiveSecuritiesNameDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US" id="id_7047976_1287793_1_1">Assets</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US" id="id_7047976_1287793_6_1">Total assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="us-gaap_AssetsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US" id="id_7047976_1273668_1_1">Assets [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US" id="id_7047976_1273668_2_1">Assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsAbstract" xlink:to="us-gaap_AssetsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US" id="id_7047976_1288812_1_1">Assets, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US" id="id_7047976_1288812_6_1">Total current assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrent" xlink:to="us-gaap_AssetsCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="us-gaap_AssetsCurrentAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US" id="id_7047976_1276921_1_1">Assets, Current [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US" id="id_7047976_1276921_2_1">Current assets:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrentAbstract" xlink:to="us-gaap_AssetsCurrentAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="us-gaap_AssetsFairValueDisclosure"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1285757_1_1">Assets, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1285757_2_1">Money market funds</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsFairValueDisclosure" xlink:to="us-gaap_AssetsFairValueDisclosure_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsFairValueDisclosureAbstract" xlink:label="us-gaap_AssetsFairValueDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsFairValueDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270294_1_1">Assets, Fair Value Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsFairValueDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270294_2_1">Assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsFairValueDisclosureAbstract" xlink:to="us-gaap_AssetsFairValueDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_BalanceSheetComponentsLineItems" xlink:label="cdna_BalanceSheetComponentsLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_BalanceSheetComponentsLineItems_lbl" xml:lang="en-US" id="id_7047976_1428193_3_1">Balance Sheet Components [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_BalanceSheetComponentsLineItems_lbl" xml:lang="en-US" id="id_7047976_1428193_1_1">Balance Sheet Components [Line Items]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xml:lang="en-US" id="id_7047976_1275350_1_1">Business Acquisition, Equity Interest Issued or Issuable, Number of Shares</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl" xml:lang="en-US" id="id_7047976_1275350_2_1">Contingent obligation to issue common stock</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:to="us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="us-gaap_BusinessAcquisitionLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xml:lang="en-US" id="id_7047976_1276962_1_1">Business Acquisition [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessAcquisitionLineItems_lbl" xml:lang="en-US" id="id_7047976_1276962_2_1">Business Acquisition [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BusinessAcquisitionLineItems" xlink:to="us-gaap_BusinessAcquisitionLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_lbl" xml:lang="en-US" id="id_7047976_1278617_1_1">Business Acquisition, Pro Forma Earnings Per Share, Basic</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_lbl" xml:lang="en-US" id="id_7047976_1278617_2_1">Net loss per common share-basic</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted_lbl" xml:lang="en-US" id="id_7047976_1273697_1_1">Business Acquisition, Pro Forma Earnings Per Share, Diluted</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionProFormaInformationTextBlock" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionProFormaInformationTextBlock_lbl" xml:lang="en-US" id="id_7047976_1275354_1_1">Business Acquisition, Pro Forma Information [Table Text Block]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_BusinessAcquisitionsProFormaAdjustmentIncreaseDecreaseInIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" id="id_7047976_1558131_3_1">Business Acquisitions Pro Forma Adjustment Increase (Decrease) in Income Tax Expense (Benefit)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_BusinessAcquisitionsProFormaAdjustmentIncreaseDecreaseInIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" id="id_7047976_1558131_1_1">Business Acquisitions Pro Forma Adjustment Increase (Decrease) in Income Tax Expense (Benefit)</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xlink:label="us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1283823_1_1">Business Acquisition, Pro Forma Net Income (Loss)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1283823_2_1">Net loss</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xml:lang="en-US" id="id_7047976_1285171_1_1">Business Acquisition, Pro Forma Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xml:lang="en-US" id="id_7047976_1285171_2_1">Net revenue</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1_lbl" xml:lang="en-US" id="id_7047976_1283824_2_1">Estimated purchase price</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_lbl" xml:lang="en-US" id="id_7047976_1284686_2_1">Estimated fair value</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xml:lang="en-US" id="id_7047976_1285772_1_1">Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_lbl" xml:lang="en-US" id="id_7047976_1285772_2_1">Change in estimated fair value of contingent consideration</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsDescription" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsDescription"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsDescription_lbl" xml:lang="en-US" id="id_7047976_1268738_1_1">Business Combination, Contingent Consideration Arrangements, Description</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationDisclosureTextBlock" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276972_1_1">Business Combination Disclosure [Text Block]</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract" xlink:label="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1475163_3_1">Business Combination Increase Decrease To Reflect Liabilities Acquired At Fair Value [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1475163_1_1">Business Combination Increase Decrease To Reflect Liabilities Acquired At Fair Value [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1475163_2_1">Business Combination Increase Decrease To Reflect Liabilities Acquired At Fair Value [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract" xlink:to="cdna_BusinessCombinationIncreaseDecreaseToReflectLiabilitiesAcquiredAtFairValueAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="us-gaap_BusinessCombinationsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessCombinationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1276978_1_1">Business Combinations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessCombinationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1276978_2_1">Business Combinations [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BusinessCombinationsAbstract" xlink:to="us-gaap_BusinessCombinationsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationsPolicy" xlink:label="us-gaap_BusinessCombinationsPolicy"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xml:lang="en-US" id="id_7047976_1280222_1_1">Business Combinations Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_BusinessCombinationsPolicy_lbl" xml:lang="en-US" id="id_7047976_1280222_2_1">Business Combinations</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BusinessCombinationsPolicy" xlink:to="us-gaap_BusinessCombinationsPolicy_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd#stpr_CA" xlink:label="stpr_CA"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="stpr_CA_lbl" xml:lang="en-US" id="id_7047976_1274833_1_1">CALIFORNIA</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="stpr_CA_lbl" xml:lang="en-US" id="id_7047976_1274833_2_1">California [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="stpr_CA" xlink:to="stpr_CA_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasedAssetsGross" xlink:label="us-gaap_CapitalLeasedAssetsGross"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasedAssetsGross_lbl" xml:lang="en-US" id="id_7047976_1287325_1_1">Capital Leased Assets, Gross</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasedAssetsGross_lbl" xml:lang="en-US" id="id_7047976_1287325_2_1">Assets purchased under capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasedAssetsGross" xlink:to="us-gaap_CapitalLeasedAssetsGross_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeaseObligationsCurrent" xlink:label="us-gaap_CapitalLeaseObligationsCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeaseObligationsCurrent_lbl" xml:lang="en-US" id="id_7047976_1284679_1_1">Capital Lease Obligations, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeaseObligationsCurrent_lbl" xml:lang="en-US" id="id_7047976_1284679_2_1">Capital leases - current portion</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_CapitalLeaseObligationsCurrent_lbl" xml:lang="en-US" id="id_7047976_1284679_14_1">Less: current portion of obligations under capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeaseObligationsCurrent" xlink:to="us-gaap_CapitalLeaseObligationsCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeaseObligationsNoncurrent" xlink:label="us-gaap_CapitalLeaseObligationsNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeaseObligationsNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1282476_1_1">Capital Lease Obligations, Noncurrent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeaseObligationsNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1282476_2_1">Long-term portion of obligations under capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeaseObligationsNoncurrent" xlink:to="us-gaap_CapitalLeaseObligationsNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDue" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDue_lbl" xml:lang="en-US" id="id_7047976_1283815_1_1">Capital Leases, Future Minimum Payments Due</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDue_lbl" xml:lang="en-US" id="id_7047976_1283815_6_1">Total minimum lease payments under capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDue" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_lbl" xml:lang="en-US" id="id_7047976_1283365_1_1">Capital Leases, Future Minimum Payments Due, Next Twelve Months</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_lbl" xml:lang="en-US" id="id_7047976_1283365_2_1">Capital Leases, 2015</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_lbl" xml:lang="en-US" id="id_7047976_1285159_1_1">Capital Leases, Future Minimum Payments Due in Four Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_lbl" xml:lang="en-US" id="id_7047976_1285159_2_1">Capital Leases, 2018</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xml:lang="en-US" id="id_7047976_1282009_1_1">Capital Leases, Future Minimum Payments Due in Three Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xml:lang="en-US" id="id_7047976_1282009_2_1">Capital Leases, 2017</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xml:lang="en-US" id="id_7047976_1282010_1_1">Capital Leases, Future Minimum Payments Due in Two Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xml:lang="en-US" id="id_7047976_1282010_2_1">Capital Leases, 2016</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter_lbl" xml:lang="en-US" id="id_7047976_1285160_1_1">Capital Leases, Future Minimum Payments Due Thereafter</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter_lbl" xml:lang="en-US" id="id_7047976_1285160_2_1">Capital Leases, 2019 and thereafter</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_lbl" xml:lang="en-US" id="id_7047976_1285261_1_1">Capital Leases, Future Minimum Payments, Interest Included in Payments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_lbl" xml:lang="en-US" id="id_7047976_1285261_14_1">Less: amounts representing interest of capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_lbl" xml:lang="en-US" id="id_7047976_1282007_1_1">Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_lbl" xml:lang="en-US" id="id_7047976_1282007_2_1">Capital Leases, Present value of minimum lease payments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_lbl" xml:lang="en-US" id="id_7047976_1282007_6_1">Capital Leases, Present value of minimum lease payments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments" xlink:to="us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US" id="id_7047976_1285262_1_1">Cash and Cash Equivalents, at Carrying Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US" id="id_7047976_1285262_4_1">Cash and cash equivalents at end of period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US" id="id_7047976_1285262_5_1">Cash and cash equivalents at beginning of period</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US" id="id_7047976_1285262_2_1">Cash and cash equivalents</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1286290_1_1">Cash and Cash Equivalents, Period Increase (Decrease)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1286290_6_1">Net increase (decrease) in cash and cash equivalents</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:to="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1275397_1_1">Cash and Cash Equivalents, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1275397_2_1">Cash Equivalents</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xml:lang="en-US" id="id_7047976_1272014_1_1">Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xml:lang="en-US" id="id_7047976_1272014_2_1">Restricted Cash</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:to="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270378_1_1">Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270378_2_1">Supplemental disclosures of noncash investing and financing activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:to="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ChangeInControlForRepayment" xlink:label="cdna_ChangeInControlForRepayment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ChangeInControlForRepayment_lbl" xml:lang="en-US" id="id_7047976_1574582_3_1">Change In Control For Repayment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ChangeInControlForRepayment_lbl" xml:lang="en-US" id="id_7047976_1574582_1_1">Change In Control For Repayment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ChangeInControlForRepayment_lbl" xml:lang="en-US" id="id_7047976_1574582_2_1">Change in control for repayment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ChangeInControlForRepayment" xlink:to="cdna_ChangeInControlForRepayment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="us-gaap_ClassOfStockDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfStockDomain_lbl" xml:lang="en-US" id="id_7047976_1277017_1_1">Class of Stock [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfStockDomain_lbl" xml:lang="en-US" id="id_7047976_1277017_2_1">Class of Stock [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfStockDomain" xlink:to="us-gaap_ClassOfStockDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="us-gaap_ClassOfWarrantOrRightAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xml:lang="en-US" id="id_7047976_1280248_1_1">Class of Warrant or Right [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xml:lang="en-US" id="id_7047976_1280248_2_1">Class of Warrant or Right [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="us-gaap_ClassOfWarrantOrRightDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xml:lang="en-US" id="id_7047976_1272026_1_1">Class of Warrant or Right [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xml:lang="en-US" id="id_7047976_1272026_2_1">Class of Warrant or Right [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" id="id_7047976_1275410_1_1">Class of Warrant or Right, Exercise Price of Warrants or Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/positiveLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" id="id_7047976_1275410_32_1">Warrants to purchase stock of convertible preferred stock, per share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" id="id_7047976_1275410_2_1">Exercise Price</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US" id="id_7047976_1275410_12_1">Warrant to purchase of common stock, per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateEightMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateEightMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateEightMember_lbl" xml:lang="en-US" id="id_7047976_1626477_3_1">Class Of Warrant Or Right Issued on July 2010 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateEightMember_lbl" xml:lang="en-US" id="id_7047976_1626477_1_1">Class Of Warrant Or Right Issued Date Eight [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateEightMember_lbl" xml:lang="en-US" id="id_7047976_1626477_2_1">Class Of Warrant Or Right Issued on July 2010 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateEightMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateEightMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateFiveMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFiveMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFiveMember_lbl" xml:lang="en-US" id="id_7047976_1626412_3_1">Class Of Warrant Or Right Issued on November 2006 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFiveMember_lbl" xml:lang="en-US" id="id_7047976_1626412_1_1">Class Of Warrant Or Right Issued Date Five [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFiveMember_lbl" xml:lang="en-US" id="id_7047976_1626412_2_1">Class Of Warrant Or Right Issued on November 2006 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateFiveMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateFiveMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateFourMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFourMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFourMember_lbl" xml:lang="en-US" id="id_7047976_1363836_3_1">Class Of Warrant Or Right Issued on July 2006 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFourMember_lbl" xml:lang="en-US" id="id_7047976_1363836_1_1">Class Of Warrant Or Right Issued Date Four [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateFourMember_lbl" xml:lang="en-US" id="id_7047976_1363836_2_1">Class Of Warrant Or Right Issued on July 2006 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateFourMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateFourMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateOneMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateOneMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateOneMember_lbl" xml:lang="en-US" id="id_7047976_1338484_3_1">Class Of Warrant Or Right Issued Date One [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateOneMember_lbl" xml:lang="en-US" id="id_7047976_1338484_1_1">Class Of Warrant Or Right Issued Date One [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateOneMember_lbl" xml:lang="en-US" id="id_7047976_1338484_2_1">Class Of Warrant Or Right Issued Date One [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateOneMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateOneMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateSevenMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSevenMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSevenMember_lbl" xml:lang="en-US" id="id_7047976_1626476_3_1">Class Of Warrant Or Right Issued on August 2009 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSevenMember_lbl" xml:lang="en-US" id="id_7047976_1626476_1_1">Class Of Warrant Or Right Issued Date Seven [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSevenMember_lbl" xml:lang="en-US" id="id_7047976_1626476_2_1">Class Of Warrant Or Right Issued on August 2009 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateSevenMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateSevenMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateSixMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSixMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSixMember_lbl" xml:lang="en-US" id="id_7047976_1626475_3_1">Class Of Warrant Or Right Issued on February 2008 [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSixMember_lbl" xml:lang="en-US" id="id_7047976_1626475_1_1">Class Of Warrant Or Right Issued Date Six [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateSixMember_lbl" xml:lang="en-US" id="id_7047976_1626475_2_1">Class Of Warrant Or Right Issued on February 2008 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateSixMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateSixMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateThreeMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateThreeMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateThreeMember_lbl" xml:lang="en-US" id="id_7047976_1485668_3_1">Class Of Warrant Or Right Issued Date Three [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateThreeMember_lbl" xml:lang="en-US" id="id_7047976_1485668_1_1">Class Of Warrant Or Right Issued Date Three [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateThreeMember_lbl" xml:lang="en-US" id="id_7047976_1485668_2_1">Class Of Warrant Or Right Issued Date Three [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateThreeMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateThreeMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightIssuedDateTwoMember" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateTwoMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateTwoMember_lbl" xml:lang="en-US" id="id_7047976_1467953_3_1">Class Of Warrant Or Right Issued Date Two [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateTwoMember_lbl" xml:lang="en-US" id="id_7047976_1467953_1_1">Class Of Warrant Or Right Issued Date Two [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightIssuedDateTwoMember_lbl" xml:lang="en-US" id="id_7047976_1467953_2_1">Class Of Warrant Or Right Issued Date Two [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightIssuedDateTwoMember" xlink:to="cdna_ClassOfWarrantOrRightIssuedDateTwoMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US" id="id_7047976_1277020_1_1">Class of Warrant or Right [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US" id="id_7047976_1277020_2_1">Class of Warrant or Right [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US" id="id_7047976_1277021_1_1">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US" id="id_7047976_1277021_2_1">Warrant to purchase of common stock, shares</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US" id="id_7047976_1277021_12_1">Warrants to purchase stock of convertible preferred stock, shares</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US" id="id_7047976_1277022_1_1">Class of Warrant or Right, Outstanding</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US" id="id_7047976_1277022_2_1">Number of Shares of Outstanding Underlying Warrant</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US" id="id_7047976_1277022_12_1">Number of Shares Outstanding Underlying Warrants</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightOutstanding" xlink:to="us-gaap_ClassOfWarrantOrRightOutstanding_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="us-gaap_ClassOfWarrantOrRightTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xml:lang="en-US" id="id_7047976_1275411_1_1">Class of Warrant or Right [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xml:lang="en-US" id="id_7047976_1275411_2_1">Class of Warrant or Right [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_ClassOfWarrantOrRightTable_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear" xlink:label="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear_lbl" xml:lang="en-US" id="id_7047976_1611779_3_1">Class of warrant or right warrant issuance month and year.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear_lbl" xml:lang="en-US" id="id_7047976_1611779_1_1">Class Of Warrant Or Right Warrant Issuance Month And Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear_lbl" xml:lang="en-US" id="id_7047976_1611779_2_1">Issue Date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear" xlink:to="cdna_ClassOfWarrantOrRightWarrantIssuanceMonthAndYear_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_CollaborativeAgreementContractValue" xlink:label="cdna_CollaborativeAgreementContractValue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_CollaborativeAgreementContractValue_lbl" xml:lang="en-US" id="id_7047976_1409097_3_1">Collaborative agreement contract value.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_CollaborativeAgreementContractValue_lbl" xml:lang="en-US" id="id_7047976_1409097_1_1">Collaborative Agreement Contract Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_CollaborativeAgreementContractValue_lbl" xml:lang="en-US" id="id_7047976_1409097_2_1">Consideration of arrangement of license</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_CollaborativeAgreementContractValue" xlink:to="cdna_CollaborativeAgreementContractValue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CollaborativeArrangementDisclosureTextBlock" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1268796_1_1">Collaborative Arrangement Disclosure [Text Block]</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CollaborativeArrangementDisclosureTextBlock" xlink:to="us-gaap_CollaborativeArrangementDisclosureTextBlock_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xml:lang="en-US" id="id_7047976_1270409_2_1">Concentration Risk Benchmark [Domain]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ContingentConsiderationClassifiedAsEquityMember_lbl" xml:lang="en-US" id="id_7047976_1280288_1_1">Contingent Consideration Classified as Equity [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ContingentConsiderationClassifiedAsEquityMember_lbl" xml:lang="en-US" id="id_7047976_1280288_2_1">Significant Unobservable Inputs (Level 3), Contingent Consideration Liability [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ContingentConsiderationMilestoneMeasurementPeriodOne_lbl" xml:lang="en-US" id="id_7047976_1552615_1_1">Contingent Consideration Milestone Measurement Period One</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ContingentConsiderationMilestoneMeasurementPeriodOne_lbl" xml:lang="en-US" id="id_7047976_1552615_2_1">Milestone measurement period</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1273774_1_1">Contingent Consideration Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ContingentConsiderationTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1273774_2_1">Contingent Consideration Type [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ContingentConsiderationTypeDomain" xlink:to="us-gaap_ContingentConsiderationTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ContingentPaymentMember" xlink:label="cdna_ContingentPaymentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ContingentPaymentMember_lbl" xml:lang="en-US" id="id_7047976_1329118_3_1">Contingent Payment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ContingentPaymentMember_lbl" xml:lang="en-US" id="id_7047976_1329118_1_1">Contingent Payment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ContingentPaymentMember_lbl" xml:lang="en-US" id="id_7047976_1329118_2_1">Contingent consideration [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ContingentPaymentMember" xlink:to="cdna_ContingentPaymentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ContractualObligationMaturityDate" xlink:label="cdna_ContractualObligationMaturityDate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ContractualObligationMaturityDate_lbl" xml:lang="en-US" id="id_7047976_1477639_3_1">Contractual Obligation Maturity Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ContractualObligationMaturityDate_lbl" xml:lang="en-US" id="id_7047976_1477639_1_1">Contractual Obligation Maturity Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ContractualObligationMaturityDate_lbl" xml:lang="en-US" id="id_7047976_1477639_2_1">Contingent consideration maturity date</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ConversionOfConvertiblePreferredStockToCommonStockAtInitialPublicOffering" xlink:label="cdna_ConversionOfConvertiblePreferredStockToCommonStockAtInitialPublicOffering"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ConversionOfConvertiblePreferredStockToCommonStockAtInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1503989_3_1">Conversion Of Convertible Preferred Stock To Common Stock At Initial Public Offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ConversionOfConvertiblePreferredStockToCommonStockAtInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1503989_1_1">Conversion Of Convertible Preferred Stock To Common Stock At Initial Public Offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ConversionOfConvertiblePreferredStockToCommonStockAtInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1503989_2_1">Conversion of convertible preferred stock to common stock upon initial public offering</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ConversionOfConvertiblePreferredStockWarrantsToCommonStockWarrants" xlink:label="cdna_ConversionOfConvertiblePreferredStockWarrantsToCommonStockWarrants"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ConversionOfConvertiblePreferredStockWarrantsToCommonStockWarrants_lbl" xml:lang="en-US" id="id_7047976_1609930_3_1">Conversion Of Convertible Preferred Stock Warrants To Common Stock Warrants</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ConversionOfConvertiblePreferredStockWarrantsToCommonStockWarrants_lbl" xml:lang="en-US" id="id_7047976_1609930_1_1">Conversion Of Convertible Preferred Stock Warrants To Common Stock Warrants</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ConversionOfConvertiblePreferredStockWarrantsToCommonStockWarrants_lbl" xml:lang="en-US" id="id_7047976_1609930_2_1">Conversion of convertible preferred stock warrants to common stock warrants upon initial public offering</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConversionOfStockAmountIssued1" xlink:label="us-gaap_ConversionOfStockAmountIssued1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConversionOfStockAmountIssued1_lbl" xml:lang="en-US" id="id_7047976_1283345_1_1">Conversion of Stock, Amount Issued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConversionOfStockAmountIssued1_lbl" xml:lang="en-US" id="id_7047976_1283345_2_1">Conversion of subordinated convertible note to common stock upon initial public offering</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConvertibleNotesPayable" xlink:label="us-gaap_ConvertibleNotesPayable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xml:lang="en-US" id="id_7047976_1283343_1_1">Convertible Notes Payable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConvertibleNotesPayable_lbl" xml:lang="en-US" id="id_7047976_1283343_2_1">Principal and interest amount of notes</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertibleNotesPayable" xlink:to="us-gaap_ConvertibleNotesPayable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConvertiblePreferredStockMember" xlink:label="us-gaap_ConvertiblePreferredStockMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1270467_1_1">Convertible Preferred Stock [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1270467_2_1">Convertible Preferred Stock [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertiblePreferredStockMember" xlink:to="us-gaap_ConvertiblePreferredStockMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion" xlink:label="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_lbl" xml:lang="en-US" id="id_7047976_1278689_1_1">Convertible Preferred Stock, Shares Issued upon Conversion</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_lbl" xml:lang="en-US" id="id_7047976_1278689_2_1">Number of shares issued for each share of convertible preferred stock</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConvertibleSubordinatedDebt" xlink:label="us-gaap_ConvertibleSubordinatedDebt"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertibleSubordinatedDebt_lbl" xml:lang="en-US" id="id_7047976_1284651_1_1">Convertible Subordinated Debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConvertibleSubordinatedDebt_lbl" xml:lang="en-US" id="id_7047976_1284651_2_1">Subordinated convertible promissory note issued</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertibleSubordinatedDebt" xlink:to="us-gaap_ConvertibleSubordinatedDebt_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ConvertibleSubordinatedDebtMember" xlink:label="us-gaap_ConvertibleSubordinatedDebtMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertibleSubordinatedDebtMember_lbl" xml:lang="en-US" id="id_7047976_1277063_1_1">Convertible Subordinated Debt [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConvertibleSubordinatedDebtMember_lbl" xml:lang="en-US" id="id_7047976_1277063_2_1">Convertible Subordinated Debt [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertibleSubordinatedDebtMember" xlink:to="us-gaap_ConvertibleSubordinatedDebtMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ConvertibleSubordinatedNotesPrincipalAmount" xlink:label="cdna_ConvertibleSubordinatedNotesPrincipalAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ConvertibleSubordinatedNotesPrincipalAmount_lbl" xml:lang="en-US" id="id_7047976_1522727_3_1">Convertible Subordinated Notes Principal Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ConvertibleSubordinatedNotesPrincipalAmount_lbl" xml:lang="en-US" id="id_7047976_1522727_1_1">Convertible Subordinated Notes Principal Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ConvertibleSubordinatedNotesPrincipalAmount_lbl" xml:lang="en-US" id="id_7047976_1522727_2_1">Principal amount of notes</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ConvertibleSubordinatedNotesPrincipalAmount" xlink:to="cdna_ConvertibleSubordinatedNotesPrincipalAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="us-gaap_CostOfSalesMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CostOfSalesMember_lbl" xml:lang="en-US" id="id_7047976_1270466_1_1">Cost of Sales [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CostOfSalesMember_lbl" xml:lang="en-US" id="id_7047976_1270466_2_1">Cost of testing [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CostOfSalesMember" xlink:to="us-gaap_CostOfSalesMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CostOfSalesPolicyTextBlock" xlink:label="us-gaap_CostOfSalesPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CostOfSalesPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1272069_1_1">Cost of Sales, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CostOfSalesPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1272069_2_1">Cost of Testing</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CostOfSalesPolicyTextBlock" xlink:to="us-gaap_CostOfSalesPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CostOfServices" xlink:label="us-gaap_CostOfServices"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CostOfServices_lbl" xml:lang="en-US" id="id_7047976_1286316_1_1">Cost of Services</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CostOfServices_lbl" xml:lang="en-US" id="id_7047976_1286316_2_1">Cost of testing</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CostsAndExpensesAbstract" xlink:label="us-gaap_CostsAndExpensesAbstract"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CostsAndExpensesAbstract_lbl" xml:lang="en-US" id="id_7047976_1275457_2_1">Operating expenses:</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CreditConcentrationRiskMember" xlink:label="us-gaap_CreditConcentrationRiskMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CreditConcentrationRiskMember_lbl" xml:lang="en-US" id="id_7047976_1277073_1_1">Credit Concentration Risk [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CreditConcentrationRiskMember_lbl" xml:lang="en-US" id="id_7047976_1277073_2_1">Credit Concentration Risk [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CreditConcentrationRiskMember" xlink:to="us-gaap_CreditConcentrationRiskMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="us-gaap_CreditFacilityAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CreditFacilityAxis_lbl" xml:lang="en-US" id="id_7047976_1275460_1_1">Credit Facility [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CreditFacilityAxis_lbl" xml:lang="en-US" id="id_7047976_1275460_2_1">Credit Facility [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CreditFacilityAxis" xlink:to="us-gaap_CreditFacilityAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="us-gaap_CreditFacilityDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CreditFacilityDomain_lbl" xml:lang="en-US" id="id_7047976_1278703_1_1">Credit Facility [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CreditFacilityDomain_lbl" xml:lang="en-US" id="id_7047976_1278703_2_1">Credit Facility [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="us-gaap_CreditFacilityDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="dei_CurrentFiscalYearEndDate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xml:lang="en-US" id="id_7047976_1276508_1_1">Current Fiscal Year End Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xml:lang="en-US" id="id_7047976_1276508_2_1">Current Fiscal Year End Date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CurrentFiscalYearEndDate" xlink:to="dei_CurrentFiscalYearEndDate_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="us-gaap_CustomerConcentrationRiskMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xml:lang="en-US" id="id_7047976_1275481_1_1">Customer Concentration Risk [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xml:lang="en-US" id="id_7047976_1275481_2_1">Customer Concentration Risk [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CustomerConcentrationRiskMember" xlink:to="us-gaap_CustomerConcentrationRiskMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xml:lang="en-US" id="id_7047976_1272083_1_1">Debt Instrument, Basis Spread on Variable Rate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xml:lang="en-US" id="id_7047976_1272083_2_1">Interest rate basis spread</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:to="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentCollateralFee" xlink:label="us-gaap_DebtInstrumentCollateralFee"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentCollateralFee_lbl" xml:lang="en-US" id="id_7047976_1287372_1_1">Debt Instrument, Collateral Fee</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentCollateralFee_lbl" xml:lang="en-US" id="id_7047976_1287372_2_1">Loan deferral additional fee</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentCollateralFee" xlink:to="us-gaap_DebtInstrumentCollateralFee_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xml:lang="en-US" id="id_7047976_1273807_1_1">Debt Instrument, Convertible, Conversion Price</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xml:lang="en-US" id="id_7047976_1273807_2_1">Convertible notes, per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:to="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments" xlink:label="us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments_lbl" xml:lang="en-US" id="id_7047976_1268866_1_1">Debt Instrument, Convertible, Number of Equity Instruments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments_lbl" xml:lang="en-US" id="id_7047976_1268866_2_1">Convertible notes, shares</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments" xlink:to="us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentDateOfFirstRequiredPayment1" xlink:label="us-gaap_DebtInstrumentDateOfFirstRequiredPayment1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentDateOfFirstRequiredPayment1_lbl" xml:lang="en-US" id="id_7047976_1275480_1_1">Debt Instrument, Date of First Required Payment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentDateOfFirstRequiredPayment1_lbl" xml:lang="en-US" id="id_7047976_1275480_2_1">Loan to defer the beginning of principal repayment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentDateOfFirstRequiredPayment1" xlink:to="us-gaap_DebtInstrumentDateOfFirstRequiredPayment1_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentDescription" xlink:label="us-gaap_DebtInstrumentDescription"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentDescription_lbl" xml:lang="en-US" id="id_7047976_1277092_1_1">Debt Instrument, Description</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentDescription_lbl" xml:lang="en-US" id="id_7047976_1277092_2_1">Loan agreement description</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentDescription" xlink:to="us-gaap_DebtInstrumentDescription_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentDescriptionOfVariableRateBasis" xlink:label="us-gaap_DebtInstrumentDescriptionOfVariableRateBasis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentDescriptionOfVariableRateBasis_lbl" xml:lang="en-US" id="id_7047976_1273822_1_1">Debt Instrument, Description of Variable Rate Basis</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentDescriptionOfVariableRateBasis_lbl" xml:lang="en-US" id="id_7047976_1273822_2_1">Interest rate, description</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentDescriptionOfVariableRateBasis" xlink:to="us-gaap_DebtInstrumentDescriptionOfVariableRateBasis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="us-gaap_DebtInstrumentFaceAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xml:lang="en-US" id="id_7047976_1283336_1_1">Debt Instrument, Face Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xml:lang="en-US" id="id_7047976_1283336_2_1">Loan and security agreement cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentFaceAmount" xlink:to="us-gaap_DebtInstrumentFaceAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_DebtInstrumentFairValueCarryingValueAbstract" xlink:label="cdna_DebtInstrumentFairValueCarryingValueAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_DebtInstrumentFairValueCarryingValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1456385_3_1">Debt Instrument Fair Value Carrying Value [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_DebtInstrumentFairValueCarryingValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1456385_1_1">Debt Instrument Fair Value Carrying Value [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_DebtInstrumentFairValueCarryingValueAbstract_lbl" xml:lang="en-US" id="id_7047976_1456385_2_1">Debt Instrument Fair Value Carrying Value [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_DebtInstrumentFairValueCarryingValueAbstract" xlink:to="cdna_DebtInstrumentFairValueCarryingValueAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentFeeAmount" xlink:label="us-gaap_DebtInstrumentFeeAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentFeeAmount_lbl" xml:lang="en-US" id="id_7047976_1285313_1_1">Debt Instrument, Fee Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentFeeAmount_lbl" xml:lang="en-US" id="id_7047976_1285313_2_1">Facility Fee amount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentFeeAmount" xlink:to="us-gaap_DebtInstrumentFeeAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentFrequencyOfPeriodicPayment" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xml:lang="en-US" id="id_7047976_1275482_1_1">Debt Instrument, Frequency of Periodic Payment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xml:lang="en-US" id="id_7047976_1275482_2_1">Loan interest description</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment" xlink:to="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xml:lang="en-US" id="id_7047976_1270470_1_1">Debt Instrument, Interest Rate, Stated Percentage</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xml:lang="en-US" id="id_7047976_1270470_2_1">Annual interest rate</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:to="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="us-gaap_DebtInstrumentLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xml:lang="en-US" id="id_7047976_1270473_1_1">Debt Instrument [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xml:lang="en-US" id="id_7047976_1270473_2_1">Debt Instrument [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentPeriodicPayment" xlink:label="us-gaap_DebtInstrumentPeriodicPayment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentPeriodicPayment_lbl" xml:lang="en-US" id="id_7047976_1286325_1_1">Debt Instrument, Periodic Payment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentPeriodicPayment_lbl" xml:lang="en-US" id="id_7047976_1286325_2_1">Interest payment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentPeriodicPayment" xlink:to="us-gaap_DebtInstrumentPeriodicPayment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentPeriodicPaymentPrincipal" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentPrincipal"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentPrincipal_lbl" xml:lang="en-US" id="id_7047976_1285831_1_1">Debt Instrument, Periodic Payment, Principal</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentPrincipal_lbl" xml:lang="en-US" id="id_7047976_1285831_2_1">Total repayment of principal</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentPeriodicPaymentPrincipal" xlink:to="us-gaap_DebtInstrumentPeriodicPaymentPrincipal_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid_lbl" xml:lang="en-US" id="id_7047976_1285130_1_1">Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid_lbl" xml:lang="en-US" id="id_7047976_1285130_2_1">Final payment due at the end of the term</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid" xlink:to="us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="us-gaap_DebtInstrumentTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentTable_lbl" xml:lang="en-US" id="id_7047976_1273820_1_1">Schedule of Long-term Debt Instruments [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DebtInstrumentTable_lbl" xml:lang="en-US" id="id_7047976_1273820_2_1">Schedule of Long-term Debt Instruments [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentTable" xlink:to="us-gaap_DebtInstrumentTable_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet_lbl" xml:lang="en-US" id="id_7047976_1288907_1_1">Debt Instrument, Unamortized Discount (Premium), Net</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" id="id_7047976_1285325_1_1">Deferred Income Tax Expense (Benefit)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xml:lang="en-US" id="id_7047976_1285325_2_1">Deferred tax benefit</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilities" xlink:label="us-gaap_DeferredIncomeTaxLiabilities"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xml:lang="en-US" id="id_7047976_1283784_1_1">Deferred Tax Liabilities, Gross</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="us-gaap_DeferredIncomeTaxLiabilities_lbl" xml:lang="en-US" id="id_7047976_1283784_19_1">Total deferred tax liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeTaxLiabilities" xlink:to="us-gaap_DeferredIncomeTaxLiabilities_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRentCreditCurrent" xlink:label="us-gaap_DeferredRentCreditCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRentCreditCurrent_lbl" xml:lang="en-US" id="id_7047976_1281966_1_1">Deferred Rent Credit, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRentCreditCurrent_lbl" xml:lang="en-US" id="id_7047976_1281966_2_1">Deferred rent - current portion</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRentCreditCurrent" xlink:to="us-gaap_DeferredRentCreditCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRentCreditNoncurrent" xlink:label="us-gaap_DeferredRentCreditNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRentCreditNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1284640_1_1">Deferred Rent Credit, Noncurrent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRentCreditNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1284640_2_1">Deferred rent, net of current portion</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRentCreditNoncurrent" xlink:to="us-gaap_DeferredRentCreditNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRevenueArrangementTypeAxis" xlink:label="us-gaap_DeferredRevenueArrangementTypeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueArrangementTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1280342_1_1">Deferred Revenue Arrangement Type [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRevenueArrangementTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1280342_2_1">Deferred Revenue Arrangement Type [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueArrangementTypeAxis" xlink:to="us-gaap_DeferredRevenueArrangementTypeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRevenueArrangementTypeDomain" xlink:label="us-gaap_DeferredRevenueArrangementTypeDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueArrangementTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1275514_1_1">Deferred Revenue [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRevenueArrangementTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1275514_2_1">Deferred Revenue [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueArrangementTypeDomain" xlink:to="us-gaap_DeferredRevenueArrangementTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="us-gaap_DeferredRevenueCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xml:lang="en-US" id="id_7047976_1284239_1_1">Deferred Revenue, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xml:lang="en-US" id="id_7047976_1284239_2_1">Deferred revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xml:lang="en-US" id="id_7047976_1284239_12_1">Previously unrecognized license fee</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueCurrent" xlink:to="us-gaap_DeferredRevenueCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredRevenueNoncurrent" xlink:label="us-gaap_DeferredRevenueNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1281965_1_1">Deferred Revenue, Noncurrent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1281965_2_1">Deferred revenue, net of current portion</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueNoncurrent" xlink:to="us-gaap_DeferredRevenueNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsGross" xlink:label="us-gaap_DeferredTaxAssetsGross"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xml:lang="en-US" id="id_7047976_1285845_1_1">Deferred Tax Assets, Gross</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_DeferredTaxAssetsGross_lbl" xml:lang="en-US" id="id_7047976_1285845_6_1">Gross deferred tax assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsGross" xlink:to="us-gaap_DeferredTaxAssetsGross_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsNet" xlink:label="us-gaap_DeferredTaxAssetsNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xml:lang="en-US" id="id_7047976_1287895_1_1">Deferred Tax Assets, Net of Valuation Allowance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_DeferredTaxAssetsNet_lbl" xml:lang="en-US" id="id_7047976_1287895_6_1">Net deferred tax assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsNet" xlink:to="us-gaap_DeferredTaxAssetsNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsNetAbstract" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xml:lang="en-US" id="id_7047976_1277112_1_1">Deferred Tax Assets, Net [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsNetAbstract_lbl" xml:lang="en-US" id="id_7047976_1277112_2_1">Deferred tax assets:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsNetAbstract" xlink:to="us-gaap_DeferredTaxAssetsNetAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1287389_1_1">Deferred Tax Assets, Operating Loss Carryforwards</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1287389_2_1">Net operating loss carryforwards</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:to="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsOther" xlink:label="us-gaap_DeferredTaxAssetsOther"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsOther_lbl" xml:lang="en-US" id="id_7047976_1286340_1_1">Deferred Tax Assets, Other</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsOther_lbl" xml:lang="en-US" id="id_7047976_1286340_2_1">Other</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsOther" xlink:to="us-gaap_DeferredTaxAssetsOther_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xlink:label="us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment_lbl" xml:lang="en-US" id="id_7047976_1287391_1_1">Deferred Tax Assets, Property, Plant and Equipment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment_lbl" xml:lang="en-US" id="id_7047976_1287391_2_1">Property and equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xlink:to="us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwards" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1288395_1_1">Deferred Tax Assets, Tax Credit Carryforwards</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1288395_2_1">Tax credit carryforwards</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards" xlink:to="us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpense" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpense"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpense_lbl" xml:lang="en-US" id="id_7047976_1287900_1_1">Deferred Tax Assets, Tax Deferred Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxAssetsTaxDeferredExpense_lbl" xml:lang="en-US" id="id_7047976_1287900_2_1">Accruals</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsTaxDeferredExpense" xlink:to="us-gaap_DeferredTaxAssetsTaxDeferredExpense_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xml:lang="en-US" id="id_7047976_1281963_1_1">Deferred Tax Assets, Valuation Allowance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DeferredTaxAssetsValuationAllowance_lbl" xml:lang="en-US" id="id_7047976_1281963_14_1">Valuation allowance</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsValuationAllowance" xlink:to="us-gaap_DeferredTaxAssetsValuationAllowance_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxLiabilitiesAbstract" xlink:label="us-gaap_DeferredTaxLiabilitiesAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxLiabilitiesAbstract_lbl" xml:lang="en-US" id="id_7047976_1270502_1_1">Deferred Tax Liabilities, Gross [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DeferredTaxLiabilitiesAbstract_lbl" xml:lang="en-US" id="id_7047976_1270502_2_1">Deferred tax liabilities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxLiabilitiesAbstract" xlink:to="us-gaap_DeferredTaxLiabilitiesAbstract_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember_lbl" xml:lang="en-US" id="id_7047976_1268953_2_1">Significant Unobservable Inputs (Level 3), Derivative Liability Related to Subordinated Convertible Note [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_DiaxonhitMember_lbl" xml:lang="en-US" id="id_7047976_1574565_3_1">Diaxonhit [Member]</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_DocumentAndEntityInformationAbstract" xlink:label="cdna_DocumentAndEntityInformationAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_DocumentAndEntityInformationAbstract_lbl" xml:lang="en-US" id="id_7047976_1430739_3_1">Document And Entity Information [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_DocumentAndEntityInformationAbstract_lbl" xml:lang="en-US" id="id_7047976_1430739_1_1">Document And Entity Information [Abstract]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="dei_DocumentFiscalPeriodFocus"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xml:lang="en-US" id="id_7047976_1279677_2_1">Document Fiscal Period Focus</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentFiscalYearFocus_lbl" xml:lang="en-US" id="id_7047976_1276510_1_1">Document Fiscal Year Focus</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_DocumentFiscalYearFocus_lbl" xml:lang="en-US" id="id_7047976_1276510_2_1">Document Fiscal Year Focus</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DomesticCountryMember" xlink:label="us-gaap_DomesticCountryMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DomesticCountryMember_lbl" xml:lang="en-US" id="id_7047976_1280458_1_1">Domestic Tax Authority [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationAcquisitionCosts_lbl" xml:lang="en-US" id="id_7047976_1388287_3_1">Effective income tax rate reconciliation acquisition costs.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationAcquisitionCosts_lbl" xml:lang="en-US" id="id_7047976_1388287_1_1">Effective Income Tax Rate Reconciliation Acquisition Costs</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationAcquisitionCosts_lbl" xml:lang="en-US" id="id_7047976_1388287_2_1">IMX acquisition costs</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EffectiveIncomeTaxRateReconciliationAcquisitionCosts" xlink:to="cdna_EffectiveIncomeTaxRateReconciliationAcquisitionCosts_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xml:lang="en-US" id="id_7047976_1278867_1_1">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xml:lang="en-US" id="id_7047976_1278867_2_1">Federal tax at statutory rate</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:to="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xml:lang="en-US" id="id_7047976_1275601_1_1">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl" xml:lang="en-US" id="id_7047976_1275601_2_1">Change in valuation allowance</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:to="us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits_lbl" xml:lang="en-US" id="id_7047976_1529947_3_1">Effective income tax rate reconciliation change in unrecognized tax benefits.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits_lbl" xml:lang="en-US" id="id_7047976_1529947_1_1">Effective Income Tax Rate Reconciliation Change In Unrecognized Tax Benefits</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits_lbl" xml:lang="en-US" id="id_7047976_1529947_2_1">Change in unrecognized tax benefits</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits" xlink:to="cdna_EffectiveIncomeTaxRateReconciliationChangeInUnrecognizedTaxBenefits_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_EffectiveIncomeTaxRateReconciliationInterestExpense" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense_lbl" xml:lang="en-US" id="id_7047976_1433654_3_1">Effective income tax rate reconciliation interest expense.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense_lbl" xml:lang="en-US" id="id_7047976_1433654_1_1">Effective Income Tax Rate Reconciliation Interest Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense_lbl" xml:lang="en-US" id="id_7047976_1433654_2_1">Interest expense</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense" xlink:to="cdna_EffectiveIncomeTaxRateReconciliationInterestExpense_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent_lbl" xml:lang="en-US" id="id_7047976_1626337_3_1">Effective income tax rate reconciliation, Liability contingent for unconsolidated subsidiary, percent.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent_lbl" xml:lang="en-US" id="id_7047976_1626337_1_1">Effective Income Tax Rate Reconciliation, Liability Contingent for Unconsolidated Subsidiary, Percent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent_lbl" xml:lang="en-US" id="id_7047976_1626337_2_1">Contingent liability for IMX acquisition</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent" xlink:to="cdna_EffectiveIncomeTaxRateReconciliationLiabilityContingentForUnconsolidatedSubsidiaryPercent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciationAndAmortizationAbstract" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciationAndAmortizationAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciationAndAmortizationAbstract_lbl" xml:lang="en-US" id="id_7047976_1275604_1_1">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Percent [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciationAndAmortizationAbstract_lbl" xml:lang="en-US" id="id_7047976_1275604_2_1">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Percent [Abstract]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xml:lang="en-US" id="id_7047976_1280452_1_1">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl" xml:lang="en-US" id="id_7047976_1280452_2_1">Stock based compensation</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost" xlink:to="us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_lbl" xml:lang="en-US" id="id_7047976_1275605_1_1">Effective Income Tax Rate Reconciliation, Other Adjustments, Percent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_lbl" xml:lang="en-US" id="id_7047976_1275605_2_1">Other</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:to="us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation_lbl" xml:lang="en-US" id="id_7047976_1611752_3_1">Effective income tax rate reconciliation, preferred stock warrant revaluation.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation_lbl" xml:lang="en-US" id="id_7047976_1611752_1_1">Effective Income Tax Rate Reconciliation, Preferred Stock Warrant Revaluation</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation_lbl" xml:lang="en-US" id="id_7047976_1611752_2_1">Preferred stock warrant revaluation</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation" xlink:to="cdna_EffectiveIncomeTaxRateReconciliationPreferredStockWarrantRevaluation_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability_lbl" xml:lang="en-US" id="id_7047976_1282865_1_1">Embedded Derivative, Fair Value of Embedded Derivative Liability</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability_lbl" xml:lang="en-US" id="id_7047976_1282865_2_1">Extinguishment of embedded derivative</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability" xlink:to="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet_lbl" xml:lang="en-US" id="id_7047976_1287425_1_1">Embedded Derivative, Fair Value of Embedded Derivative, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet_lbl" xml:lang="en-US" id="id_7047976_1287425_2_1">Estimated fair value of embedded derivative liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet" xlink:to="us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1284606_1_1">Employee-related Liabilities, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1284606_2_1">Accrued payroll liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:to="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_lbl" xml:lang="en-US" id="id_7047976_1286388_1_1">Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_lbl" xml:lang="en-US" id="id_7047976_1286388_2_1">Share-based compensation costs, capitalized</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xml:lang="en-US" id="id_7047976_1270610_1_1">Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xml:lang="en-US" id="id_7047976_1270610_2_1">Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_lbl" xml:lang="en-US" id="id_7047976_1272251_1_1">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCentralIndexKey_lbl" xml:lang="en-US" id="id_7047976_1278115_1_1">Entity Central Index Key</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="dei_EntityCommonStockSharesOutstanding"/>
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    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="dei_EntityCurrentReportingStatus"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCurrentReportingStatus_lbl" xml:lang="en-US" id="id_7047976_1281311_1_1">Entity Current Reporting Status</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_EntityDomain_lbl" xml:lang="en-US" id="id_7047976_1273139_2_1">Entity [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityDomain" xlink:to="dei_EntityDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="dei_EntityFilerCategory"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityFilerCategory_lbl" xml:lang="en-US" id="id_7047976_1271511_1_1">Entity Filer Category</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityPublicFloat" xlink:label="dei_EntityPublicFloat"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityPublicFloat_lbl" xml:lang="en-US" id="id_7047976_1284726_1_1">Entity Public Float</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_EntityPublicFloat_lbl" xml:lang="en-US" id="id_7047976_1284726_2_1">Entity Public Float</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityPublicFloat" xlink:to="dei_EntityPublicFloat_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityRegistrantName_lbl" xml:lang="en-US" id="id_7047976_1269875_1_1">Entity Registrant Name</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_EntityRegistrantName_lbl" xml:lang="en-US" id="id_7047976_1269875_2_1">Entity Registrant Name</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityRegistrantName" xlink:to="dei_EntityRegistrantName_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityVoluntaryFilers" xlink:label="dei_EntityVoluntaryFilers"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityVoluntaryFilers_lbl" xml:lang="en-US" id="id_7047976_1271521_1_1">Entity Voluntary Filers</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityVoluntaryFilers" xlink:to="dei_EntityVoluntaryFilers_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="dei_EntityWellKnownSeasonedIssuer"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xml:lang="en-US" id="id_7047976_1269876_1_1">Entity Well-known Seasoned Issuer</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquipmentMember" xlink:label="us-gaap_EquipmentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1273964_1_1">Equipment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1273964_2_1">Laboratory equipment [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquipmentMember" xlink:to="us-gaap_EquipmentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquityAbstract_lbl" xml:lang="en-US" id="id_7047976_1269012_1_1">Equity [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EquityAbstract_lbl" xml:lang="en-US" id="id_7047976_1269012_2_1">Equity [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_EquityAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain" xlink:label="us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_lbl" xml:lang="en-US" id="id_7047976_1278894_2_1">Equity-Based Arrangements, Individual Contracts, Type of Deferred Compensation [Domain]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquityComponentDomain_lbl" xml:lang="en-US" id="id_7047976_1272258_1_1">Equity Component [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EquityComponentDomain_lbl" xml:lang="en-US" id="id_7047976_1272258_2_1">Equity Component [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_EquityComponentDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" xlink:label="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract_lbl" xml:lang="en-US" id="id_7047976_1386421_3_1">Equity Method Investments And Cost Method Investments [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract_lbl" xml:lang="en-US" id="id_7047976_1386421_1_1">Equity Method Investments And Cost Method Investments [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract_lbl" xml:lang="en-US" id="id_7047976_1386421_2_1">Equity Method Investments And Cost Method Investments [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" xlink:to="cdna_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ExercisePriceRangeFourMember" xlink:label="cdna_ExercisePriceRangeFourMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ExercisePriceRangeFourMember_lbl" xml:lang="en-US" id="id_7047976_1372040_3_1">Exercise Price Range Four [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ExercisePriceRangeFourMember_lbl" xml:lang="en-US" id="id_7047976_1372040_1_1">Exercise Price Range Four [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ExercisePriceRangeFourMember_lbl" xml:lang="en-US" id="id_7047976_1372040_2_1">$7.03-12.40 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ExercisePriceRangeFourMember" xlink:to="cdna_ExercisePriceRangeFourMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ExercisePriceRangeOneMember" xlink:label="cdna_ExercisePriceRangeOneMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ExercisePriceRangeOneMember_lbl" xml:lang="en-US" id="id_7047976_1317999_3_1">Exercise Price Range One [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ExercisePriceRangeOneMember_lbl" xml:lang="en-US" id="id_7047976_1317999_1_1">Exercise Price Range One [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ExercisePriceRangeOneMember_lbl" xml:lang="en-US" id="id_7047976_1317999_2_1">$0.27-0.55 [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_ExercisePriceRangeOneMember" xlink:to="cdna_ExercisePriceRangeOneMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ExercisePriceRangeThreeMember" xlink:label="cdna_ExercisePriceRangeThreeMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ExercisePriceRangeThreeMember_lbl" xml:lang="en-US" id="id_7047976_1559791_3_1">Exercise Price Range Three [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ExercisePriceRangeThreeMember_lbl" xml:lang="en-US" id="id_7047976_1559791_1_1">Exercise Price Range Three [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ExercisePriceRangeThreeMember_lbl" xml:lang="en-US" id="id_7047976_1559791_2_1">$3.36-3.97 [Member]</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_ExercisePriceRangeTwoMember" xlink:label="cdna_ExercisePriceRangeTwoMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_ExercisePriceRangeTwoMember_lbl" xml:lang="en-US" id="id_7047976_1562377_3_1">Exercise Price Range Two [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ExercisePriceRangeTwoMember_lbl" xml:lang="en-US" id="id_7047976_1562377_1_1">Exercise Price Range Two [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_ExercisePriceRangeTwoMember_lbl" xml:lang="en-US" id="id_7047976_1562377_2_1">$2.05-3.01 [Member]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:label="us-gaap_FairValueAdjustmentOfWarrants"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US" id="id_7047976_1286409_1_1">Fair Value Adjustment of Warrants</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US" id="id_7047976_1286409_2_1">Estimated fair value of warrants</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US" id="id_7047976_1286409_12_1">Revaluation of warrants and derivatives to estimated fair value</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisInstrumentsClassifiedInShareholdersEquityPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1269068_1_1">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Instruments Classified in Shareholders' Equity, Period Increase (Decrease)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisInstrumentsClassifiedInShareholdersEquityPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1269068_2_1">Reclassification to stockholders' equity</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_lbl" xml:lang="en-US" id="id_7047976_1283239_1_1">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_lbl" xml:lang="en-US" id="id_7047976_1283239_2_1">Issuance of financial instruments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1277300_1_1">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease_lbl" xml:lang="en-US" id="id_7047976_1277300_2_1">Change in estimated fair value</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US" id="id_7047976_1284181_1_1">Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US" id="id_7047976_1284181_4_1">Ending Balance</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US" id="id_7047976_1284181_5_1">Beginning Balance</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems" xlink:label="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems_lbl" xml:lang="en-US" id="id_7047976_1344687_3_1">Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems_lbl" xml:lang="en-US" id="id_7047976_1344687_1_1">Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems_lbl" xml:lang="en-US" id="id_7047976_1344687_2_1">Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems" xlink:to="cdna_FairValueOfAssetsAndLiabilitiesMeasuredOnNonRecurringBasisLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xml:lang="en-US" id="id_7047976_1280532_1_1">Fair Value of Financial Instruments, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xml:lang="en-US" id="id_7047976_1280532_2_1">Fair Value of Financial Instruments</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xml:lang="en-US" id="id_7047976_1283708_2_1">Accumulated amortization of intangible asset</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FinitelivedIntangibleAssetsAcquired1" xlink:label="us-gaap_FinitelivedIntangibleAssetsAcquired1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FinitelivedIntangibleAssetsAcquired1_lbl" xml:lang="en-US" id="id_7047976_1289002_1_1">Finite-lived Intangible Assets Acquired</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FinitelivedIntangibleAssetsAcquired1_lbl" xml:lang="en-US" id="id_7047976_1289002_2_1">Assets acquired in business combination, estimated fair value</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xml:lang="en-US" id="id_7047976_1277337_1_1">Finite-Lived Intangible Assets by Major Class [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xml:lang="en-US" id="id_7047976_1277337_2_1">Finite-Lived Intangible Assets by Major Class [Axis]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xml:lang="en-US" id="id_7047976_1272379_1_1">Finite-Lived Intangible Assets, Major Class Name [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xml:lang="en-US" id="id_7047976_1272379_2_1">Finite-Lived Intangible Assets, Major Class Name [Domain]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xml:lang="en-US" id="id_7047976_1277333_1_1">Finite-Lived Intangible Asset, Useful Life</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xml:lang="en-US" id="id_7047976_1277333_2_1">Estimated remaining useful life of patent</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="us-gaap_FurnitureAndFixturesMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xml:lang="en-US" id="id_7047976_1274094_1_1">Furniture and Fixtures [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FurnitureAndFixturesMember_lbl" xml:lang="en-US" id="id_7047976_1274094_2_1">Furniture and Fixtures [Member]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_lbl" xml:lang="en-US" id="id_7047976_1285012_2_1">Less: gain on extinguishment of derivative related to subordinated convertible note</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xml:lang="en-US" id="id_7047976_1288487_2_1">General and administrative</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xml:lang="en-US" id="id_7047976_1269133_2_1">General and administrative [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_Goodwill_lbl" xml:lang="en-US" id="id_7047976_1285421_2_1">Goodwill</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_Goodwill_lbl" xml:lang="en-US" id="id_7047976_1285421_12_1">Goodwill acquired in business combination, estimated fair value</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xml:lang="en-US" id="id_7047976_1272476_2_1">Income Statement [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeStatementAbstract_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xml:lang="en-US" id="id_7047976_1274159_2_1">Income Statement Location [Axis]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xml:lang="en-US" id="id_7047976_1270824_1_1">Income Statement Location [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xml:lang="en-US" id="id_7047976_1270824_2_1">Income Statement Location [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_IncomeStatementLocationDomain_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxAuthorityAxis_lbl" xml:lang="en-US" id="id_7047976_1280651_2_1">Income Tax Authority [Axis]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xml:lang="en-US" id="id_7047976_1279066_1_1">Income Tax Authority [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxAuthorityDomain_lbl" xml:lang="en-US" id="id_7047976_1279066_2_1">Income Tax Authority [Domain]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1272478_2_1">Income Tax Disclosure [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxDisclosureAbstract" xlink:to="us-gaap_IncomeTaxDisclosureAbstract_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1277417_2_1">Income Taxes</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_IncomeTaxesDisclosureLineItems_lbl" xml:lang="en-US" id="id_7047976_1308565_1_1">Income Taxes Disclosure [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_IncomeTaxesDisclosureLineItems_lbl" xml:lang="en-US" id="id_7047976_1308565_2_1">Income Taxes Disclosure [Line Items]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_IncomeTaxesDisclosureTable_lbl" xml:lang="en-US" id="id_7047976_1505256_3_1">Income Taxes Disclosure [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_IncomeTaxesDisclosureTable_lbl" xml:lang="en-US" id="id_7047976_1505256_1_1">Income Taxes Disclosure [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_IncomeTaxesDisclosureTable_lbl" xml:lang="en-US" id="id_7047976_1505256_2_1">Income Taxes Disclosure [Table]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1285447_2_1">Deferred revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInDeferredRevenue" xlink:to="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInInterestPayableNet" xlink:label="us-gaap_IncreaseDecreaseInInterestPayableNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInInterestPayableNet_lbl" xml:lang="en-US" id="id_7047976_1287018_1_1">Increase (Decrease) in Interest Payable, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInInterestPayableNet_lbl" xml:lang="en-US" id="id_7047976_1287018_2_1">Decrease in interest expense</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInInterestPayableNet" xlink:to="us-gaap_IncreaseDecreaseInInterestPayableNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="us-gaap_IncreaseDecreaseInInventories"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xml:lang="en-US" id="id_7047976_1282774_1_1">Increase (Decrease) in Inventories</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xml:lang="en-US" id="id_7047976_1282774_14_1">Inventory</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInInventories" xlink:to="us-gaap_IncreaseDecreaseInInventories_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US" id="id_7047976_1279090_1_1">Increase (Decrease) in Operating Capital [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US" id="id_7047976_1279090_2_1">Changes in operating assets and liabilities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInOtherAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xml:lang="en-US" id="id_7047976_1287522_1_1">Increase (Decrease) in Other Accrued Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xml:lang="en-US" id="id_7047976_1287522_2_1">Accrued and other liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities" xlink:to="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidExpensesOther" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpensesOther"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpensesOther_lbl" xml:lang="en-US" id="id_7047976_1283659_1_1">Increase (Decrease) in Prepaid Expenses, Other</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpensesOther_lbl" xml:lang="en-US" id="id_7047976_1283659_14_1">Prepaid and other assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInPrepaidExpensesOther" xlink:to="us-gaap_IncreaseDecreaseInPrepaidExpensesOther_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInRoyaltiesPayable" xlink:label="us-gaap_IncreaseDecreaseInRoyaltiesPayable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInRoyaltiesPayable_lbl" xml:lang="en-US" id="id_7047976_1289053_1_1">Increase (Decrease) in Royalties Payable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInRoyaltiesPayable_lbl" xml:lang="en-US" id="id_7047976_1289053_2_1">Accrued royalties</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInRoyaltiesPayable" xlink:to="us-gaap_IncreaseDecreaseInRoyaltiesPayable_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_IncreaseDecreaseInServicerPayables" xlink:label="cdna_IncreaseDecreaseInServicerPayables"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_IncreaseDecreaseInServicerPayables_lbl" xml:lang="en-US" id="id_7047976_1542771_3_1">Increase decrease in servicer payables.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_IncreaseDecreaseInServicerPayables_lbl" xml:lang="en-US" id="id_7047976_1542771_1_1">Increase Decrease In Servicer Payables</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_IncreaseDecreaseInServicerPayables_lbl" xml:lang="en-US" id="id_7047976_1542771_2_1">Decrease in cost of testing</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_IncreaseDecreaseInServicerPayables" xlink:to="cdna_IncreaseDecreaseInServicerPayables_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xml:lang="en-US" id="id_7047976_1269185_1_1">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl" xml:lang="en-US" id="id_7047976_1269185_2_1">Shares of common stock subject to conversion from subordinated convertible note</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities" xlink:to="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock_lbl" xml:lang="en-US" id="id_7047976_1277424_1_1">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock_lbl" xml:lang="en-US" id="id_7047976_1277424_2_1">Shares of common stock subject to conversion from preferred stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock" xlink:to="us-gaap_IncrementalCommonSharesAttributableToConversionOfPreferredStock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xml:lang="en-US" id="id_7047976_1272489_1_1">Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xml:lang="en-US" id="id_7047976_1272489_2_1">Shares of common stock subject to outstanding options</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:to="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_InitialPublicOfferingDateOfCompletion" xlink:label="cdna_InitialPublicOfferingDateOfCompletion"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_InitialPublicOfferingDateOfCompletion_lbl" xml:lang="en-US" id="id_7047976_1525671_3_1">Initial Public Offering Date Of Completion</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_InitialPublicOfferingDateOfCompletion_lbl" xml:lang="en-US" id="id_7047976_1525671_1_1">Initial Public Offering Date Of Completion</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_InitialPublicOfferingDateOfCompletion_lbl" xml:lang="en-US" id="id_7047976_1525671_2_1">Initial Public offering, closing date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_InitialPublicOfferingDateOfCompletion" xlink:to="cdna_InitialPublicOfferingDateOfCompletion_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_InitialPublicOfferingPolicyTextBlock" xlink:label="cdna_InitialPublicOfferingPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_InitialPublicOfferingPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1522983_3_1">Initial Public Offering [ Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_InitialPublicOfferingPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1522983_1_1">Initial Public Offering [ Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_InitialPublicOfferingPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1522983_2_1">Initial Public Offering</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_InitialPublicOfferingPolicyTextBlock" xlink:to="cdna_InitialPublicOfferingPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InProcessResearchAndDevelopmentMember" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xml:lang="en-US" id="id_7047976_1279083_1_1">In Process Research and Development [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InProcessResearchAndDevelopmentMember_lbl" xml:lang="en-US" id="id_7047976_1279083_2_1">In-process technology [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InProcessResearchAndDevelopmentMember" xlink:to="us-gaap_InProcessResearchAndDevelopmentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xml:lang="en-US" id="id_7047976_1288540_1_1">Intangible Assets, Net (Excluding Goodwill)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl" xml:lang="en-US" id="id_7047976_1288540_2_1">Intangible assets, net</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:to="us-gaap_IntangibleAssetsNetExcludingGoodwill_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="us-gaap_InterestExpenseDebt"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestExpenseDebt_lbl" xml:lang="en-US" id="id_7047976_1286006_1_1">Interest Expense, Debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestExpenseDebt_lbl" xml:lang="en-US" id="id_7047976_1286006_2_1">Interest expense</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpenseDebt" xlink:to="us-gaap_InterestExpenseDebt_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="us-gaap_InterestIncomeExpenseNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xml:lang="en-US" id="id_7047976_1281809_1_1">Interest Income (Expense), Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestIncomeExpenseNet_lbl" xml:lang="en-US" id="id_7047976_1281809_2_1">Interest expense, net</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestIncomeExpenseNet" xlink:to="us-gaap_InterestIncomeExpenseNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestOnConvertibleDebtNetOfTax" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax_lbl" xml:lang="en-US" id="id_7047976_1284522_1_1">Interest on Convertible Debt, Net of Tax</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax_lbl" xml:lang="en-US" id="id_7047976_1284522_2_1">Add: interest expense related to subordinated convertible note</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestOnConvertibleDebtNetOfTax" xlink:to="us-gaap_InterestOnConvertibleDebtNetOfTax_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestPaidNet" xlink:label="us-gaap_InterestPaidNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestPaidNet_lbl" xml:lang="en-US" id="id_7047976_1284085_1_1">Interest Paid, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestPaidNet_lbl" xml:lang="en-US" id="id_7047976_1284085_2_1">Cash paid for interest</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestPaidNet" xlink:to="us-gaap_InterestPaidNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="us-gaap_InventoryDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270865_1_1">Inventory Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1270865_2_1">Inventory Disclosure [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InventoryDisclosureAbstract" xlink:to="us-gaap_InventoryDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xml:lang="en-US" id="id_7047976_1287054_1_1">Inventory, Finished Goods, Net of Reserves</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl" xml:lang="en-US" id="id_7047976_1287054_2_1">Finished Goods</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:to="us-gaap_InventoryFinishedGoodsNetOfReserves_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InventoryNet_lbl" xml:lang="en-US" id="id_7047976_1288055_1_1">Inventory, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InventoryNet_lbl" xml:lang="en-US" id="id_7047976_1288055_2_1">Inventory</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_InventoryNet_lbl" xml:lang="en-US" id="id_7047976_1288055_6_1">Total Inventory</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InventoryPolicyTextBlock" xlink:label="us-gaap_InventoryPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1269208_1_1">Inventory, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1269208_2_1">Inventory</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InventoryPolicyTextBlock" xlink:to="us-gaap_InventoryPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InventoryRawMaterialsNetOfReserves" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xml:lang="en-US" id="id_7047976_1288057_1_1">Inventory, Raw Materials, Net of Reserves</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_lbl" xml:lang="en-US" id="id_7047976_1288057_2_1">Raw Materials</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InventoryRawMaterialsNetOfReserves" xlink:to="us-gaap_InventoryRawMaterialsNetOfReserves_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IPOMember" xlink:label="us-gaap_IPOMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IPOMember_lbl" xml:lang="en-US" id="id_7047976_1272538_1_1">IPO [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IPOMember_lbl" xml:lang="en-US" id="id_7047976_1272538_2_1">IPO [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IPOMember" xlink:to="us-gaap_IPOMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_IssuanceOfCommonStockInInitialPublicOfferingShares" xlink:label="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares_lbl" xml:lang="en-US" id="id_7047976_1323020_3_1">Issuance Of Common Stock In Initial Public Offering Shares</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares_lbl" xml:lang="en-US" id="id_7047976_1323020_1_1">Issuance Of Common Stock In Initial Public Offering Shares</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares_lbl" xml:lang="en-US" id="id_7047976_1323020_2_1">Issuance of common stock upon initial public offering, net of offering costs, Shares</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares" xlink:to="cdna_IssuanceOfCommonStockInInitialPublicOfferingShares_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_IssuanceOfCommonStockInitialPublicOffering" xlink:label="cdna_IssuanceOfCommonStockInitialPublicOffering"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_IssuanceOfCommonStockInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1568872_3_1">Issuance Of Common Stock Initial Public Offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_IssuanceOfCommonStockInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1568872_1_1">Issuance Of Common Stock Initial Public Offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_IssuanceOfCommonStockInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1568872_2_1">Issuance of common stock upon initial public offering, net of offering costs</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_IssuanceOfCommonStockInitialPublicOffering" xlink:to="cdna_IssuanceOfCommonStockInitialPublicOffering_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LaboratoryComputerAndOfficeEquipmentMember" xlink:label="cdna_LaboratoryComputerAndOfficeEquipmentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LaboratoryComputerAndOfficeEquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1624499_3_1">Laboratory, Computer And Office Equipment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LaboratoryComputerAndOfficeEquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1624499_1_1">Laboratory, Computer And Office Equipment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_LaboratoryComputerAndOfficeEquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1624499_2_1">Laboratory equipment and computer and office equipment [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LaboratoryComputerAndOfficeEquipmentMember" xlink:to="cdna_LaboratoryComputerAndOfficeEquipmentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LaboratoryCorpOfAmericaHoldingsMember" xlink:label="cdna_LaboratoryCorpOfAmericaHoldingsMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LaboratoryCorpOfAmericaHoldingsMember_lbl" xml:lang="en-US" id="id_7047976_1323946_3_1">Laboratory Corp Of America Holdings [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LaboratoryCorpOfAmericaHoldingsMember_lbl" xml:lang="en-US" id="id_7047976_1323946_1_1">Laboratory Corp Of America Holdings [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_LaboratoryCorpOfAmericaHoldingsMember_lbl" xml:lang="en-US" id="id_7047976_1323946_2_1">Laboratory Corp of America Holdings [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LaboratoryCorpOfAmericaHoldingsMember" xlink:to="cdna_LaboratoryCorpOfAmericaHoldingsMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="us-gaap_LeaseholdImprovementsMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xml:lang="en-US" id="id_7047976_1277482_1_1">Leasehold Improvements [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xml:lang="en-US" id="id_7047976_1277482_2_1">Leasehold improvements [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LeaseholdImprovementsMember" xlink:to="us-gaap_LeaseholdImprovementsMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_LegalEntityAxis_lbl" xml:lang="en-US" id="id_7047976_1281318_1_1">Legal Entity [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_LegalEntityAxis_lbl" xml:lang="en-US" id="id_7047976_1281318_2_1">Legal Entity [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_LegalEntityAxis" xlink:to="dei_LegalEntityAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US" id="id_7047976_1284515_1_1">Liabilities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US" id="id_7047976_1284515_6_1">Total liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Liabilities" xlink:to="us-gaap_Liabilities_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US" id="id_7047976_1283630_1_1">Liabilities and Equity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US" id="id_7047976_1283630_6_1">Total liabilities, convertible preferred stock and stockholders' equity (deficit)</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US" id="id_7047976_1275871_1_1">Liabilities and Equity [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US" id="id_7047976_1275871_2_1">Liabilities, convertible preferred stock, and stockholders' equity (deficit)</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1282281_1_1">Liabilities, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1282281_6_1">Total current liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="us-gaap_LiabilitiesCurrentAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US" id="id_7047976_1272565_1_1">Liabilities, Current [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US" id="id_7047976_1272565_2_1">Current liabilities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_LiabilitiesCurrentAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="us-gaap_LiabilitiesFairValueDisclosure"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1284516_1_1">Financial and Nonfinancial Liabilities, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1284516_6_1">Total liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesFairValueDisclosure" xlink:to="us-gaap_LiabilitiesFairValueDisclosure_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract" xlink:label="us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesFairValueDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1277488_1_1">Liabilities, Fair Value Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesFairValueDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1277488_2_1">Liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesFairValueDisclosureAbstract" xlink:to="us-gaap_LiabilitiesFairValueDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LicenseAndServicesRevenue" xlink:label="us-gaap_LicenseAndServicesRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LicenseAndServicesRevenue_lbl" xml:lang="en-US" id="id_7047976_1282734_1_1">License and Services Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LicenseAndServicesRevenue_lbl" xml:lang="en-US" id="id_7047976_1282734_2_1">Collaboration and license revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LicenseAndServicesRevenue" xlink:to="us-gaap_LicenseAndServicesRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LicensesRevenue" xlink:label="us-gaap_LicensesRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LicensesRevenue_lbl" xml:lang="en-US" id="id_7047976_1282735_1_1">Licenses Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LicensesRevenue_lbl" xml:lang="en-US" id="id_7047976_1282735_2_1">Revenue recognized under collaboration and licensing agreements</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LicensesRevenue" xlink:to="us-gaap_LicensesRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1282265_1_1">Line of Credit Facility, Current Borrowing Capacity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1282265_2_1">Loan agreement, amount borrowed</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity" xlink:to="us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityInitiationDate1" xlink:label="us-gaap_LineOfCreditFacilityInitiationDate1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityInitiationDate1_lbl" xml:lang="en-US" id="id_7047976_1269269_1_1">Line of Credit Facility, Initiation Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LineOfCreditFacilityInitiationDate1_lbl" xml:lang="en-US" id="id_7047976_1269269_2_1">Loan agreement initiation date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityInitiationDate1" xlink:to="us-gaap_LineOfCreditFacilityInitiationDate1_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1284501_1_1">Line of Credit Facility, Maximum Borrowing Capacity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1284501_2_1">Aggregate principal amount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:to="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1284941_1_1">Line of Credit Facility, Remaining Borrowing Capacity</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_lbl" xml:lang="en-US" id="id_7047976_1284941_2_1">Loan agreement, amount available to borrow</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:to="us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebt" xlink:label="us-gaap_LongTermDebt"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebt_lbl" xml:lang="en-US" id="id_7047976_1284933_1_1">Long-term Debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LongTermDebt_lbl" xml:lang="en-US" id="id_7047976_1284933_2_1">Equals: debt balance as of December 31, 2014 including accrued interest, net of unaccreted discount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LongTermDebt_lbl" xml:lang="en-US" id="id_7047976_1284933_6_1">Equals: debt balance as of December 31, 2014 including accrued interest, net of unaccreted discount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_LongTermDebt_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="us-gaap_LongTermDebtCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xml:lang="en-US" id="id_7047976_1283151_1_1">Long-term Debt, Current Maturities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xml:lang="en-US" id="id_7047976_1283151_2_1">Current portion of long-term debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xml:lang="en-US" id="id_7047976_1283151_14_1">Less: current portion</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtCurrent" xlink:to="us-gaap_LongTermDebtCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LongTermDebtMaturitiesRepayments" xlink:label="cdna_LongTermDebtMaturitiesRepayments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LongTermDebtMaturitiesRepayments_lbl" xml:lang="en-US" id="id_7047976_1611007_3_1">Long term debt maturities repayments.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LongTermDebtMaturitiesRepayments_lbl" xml:lang="en-US" id="id_7047976_1611007_1_1">Long Term Debt Maturities Repayments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="cdna_LongTermDebtMaturitiesRepayments_lbl" xml:lang="en-US" id="id_7047976_1611007_6_1">Total remaining debt payments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LongTermDebtMaturitiesRepayments" xlink:to="cdna_LongTermDebtMaturitiesRepayments_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths_lbl" xml:lang="en-US" id="id_7047976_1611005_3_1">Long term debt maturities repayments in next twelve months.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths_lbl" xml:lang="en-US" id="id_7047976_1611005_1_1">Long Term Debt Maturities Repayments In Next Twelve Months</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths_lbl" xml:lang="en-US" id="id_7047976_1611005_2_1">Year ending December 31, 2015</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths" xlink:to="cdna_LongTermDebtMaturitiesRepaymentsInNextTwelveMonths_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LongTermDebtMaturitiesRepaymentsInYearTwo" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo_lbl" xml:lang="en-US" id="id_7047976_1611006_3_1">Long term debt maturities repayments in year two.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo_lbl" xml:lang="en-US" id="id_7047976_1611006_1_1">Long Term Debt Maturities Repayments In Year Two</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo_lbl" xml:lang="en-US" id="id_7047976_1611006_2_1">Year ending December 31, 2016</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo" xlink:to="cdna_LongTermDebtMaturitiesRepaymentsInYearTwo_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LongTermDebtMaturitiesRepaymentsOfInterest" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfInterest"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfInterest_lbl" xml:lang="en-US" id="id_7047976_1492413_3_1">Long Term Debt Maturities Repayments Of Interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfInterest_lbl" xml:lang="en-US" id="id_7047976_1492413_1_1">Long Term Debt Maturities Repayments Of Interest</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfInterest_lbl" xml:lang="en-US" id="id_7047976_1492413_14_1">Less: amounts representing interest</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LongTermDebtMaturitiesRepaymentsOfInterest" xlink:to="cdna_LongTermDebtMaturitiesRepaymentsOfInterest_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal_lbl" xml:lang="en-US" id="id_7047976_1379422_3_1">Long Term Debt Maturities Repayments Of Principal</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal_lbl" xml:lang="en-US" id="id_7047976_1379422_1_1">Long Term Debt Maturities Repayments Of Principal</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal_lbl" xml:lang="en-US" id="id_7047976_1379422_6_1">Equals: debt principal balance as of December 31, 2014</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal" xlink:to="cdna_LongTermDebtMaturitiesRepaymentsOfPrincipal_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="us-gaap_LongTermDebtNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1283604_1_1">Long-term Debt, Excluding Current Maturities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1283604_2_1">Long-term portion</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1283604_12_1">Long-term portion of debt and other, net of current portion</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtNoncurrent" xlink:to="us-gaap_LongTermDebtNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="us-gaap_LongtermDebtTypeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1279211_1_1">Long-term Debt, Type [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1279211_2_1">Long-term Debt, Type [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongtermDebtTypeAxis" xlink:to="us-gaap_LongtermDebtTypeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="us-gaap_LongtermDebtTypeDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1270935_1_1">Long-term Debt, Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1270935_2_1">Long-term Debt, Type [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongtermDebtTypeDomain" xlink:to="us-gaap_LongtermDebtTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="us-gaap_LossContingenciesLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LossContingenciesLineItems_lbl" xml:lang="en-US" id="id_7047976_1280798_1_1">Loss Contingencies [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LossContingenciesLineItems_lbl" xml:lang="en-US" id="id_7047976_1280798_2_1">Loss Contingencies [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LossContingenciesLineItems" xlink:to="us-gaap_LossContingenciesLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="us-gaap_LossContingenciesTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LossContingenciesTable_lbl" xml:lang="en-US" id="id_7047976_1279197_1_1">Loss Contingencies [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LossContingenciesTable_lbl" xml:lang="en-US" id="id_7047976_1279197_2_1">Loss Contingencies [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LossContingenciesTable" xlink:to="us-gaap_LossContingenciesTable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencySettlementAgreementCounterpartysName" xlink:label="us-gaap_LossContingencySettlementAgreementCounterpartysName"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LossContingencySettlementAgreementCounterpartysName_lbl" xml:lang="en-US" id="id_7047976_1280802_1_1">Loss Contingency, Settlement Agreement, Counterparty's Name</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LossContingencySettlementAgreementCounterpartysName_lbl" xml:lang="en-US" id="id_7047976_1280802_2_1">Settlement and mutual release agreement, counter party name</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LossContingencySettlementAgreementCounterpartysName" xlink:to="us-gaap_LossContingencySettlementAgreementCounterpartysName_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencySettlementAgreementDate" xlink:label="us-gaap_LossContingencySettlementAgreementDate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LossContingencySettlementAgreementDate_lbl" xml:lang="en-US" id="id_7047976_1275935_1_1">Loss Contingency, Settlement Agreement, Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LossContingencySettlementAgreementDate_lbl" xml:lang="en-US" id="id_7047976_1275935_2_1">Settlement and mutual release agreement, date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LossContingencySettlementAgreementDate" xlink:to="us-gaap_LossContingencySettlementAgreementDate_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencySettlementAgreementTerms" xlink:label="us-gaap_LossContingencySettlementAgreementTerms"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LossContingencySettlementAgreementTerms_lbl" xml:lang="en-US" id="id_7047976_1275936_1_1">Loss Contingency, Settlement Agreement, Terms</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LossContingencySettlementAgreementTerms_lbl" xml:lang="en-US" id="id_7047976_1275936_2_1">Settlement and mutual release agreement, terms of agreement</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LossContingencySettlementAgreementTerms" xlink:to="us-gaap_LossContingencySettlementAgreementTerms_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorCustomersAxis" xlink:label="us-gaap_MajorCustomersAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MajorCustomersAxis_lbl" xml:lang="en-US" id="id_7047976_1275930_1_1">Customer [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MajorCustomersAxis_lbl" xml:lang="en-US" id="id_7047976_1275930_2_1">Customer [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MajorCustomersAxis" xlink:to="us-gaap_MajorCustomersAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1282255_1_1">Mandatorily Redeemable Preferred Stock, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1282255_2_1">Warrants to purchase convertible preferred stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure" xlink:to="us-gaap_MandatorilyRedeemablePreferredStockFairValueDisclosure_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MandatorilyRedeemablePreferredStockMember" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1269312_1_1">Mandatorily Redeemable Preferred Stock [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MandatorilyRedeemablePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1269312_2_1">Significant Unobservable Inputs (Level 3), Warrants to Purchase Convertible Preferred Stock [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MandatorilyRedeemablePreferredStockMember" xlink:to="us-gaap_MandatorilyRedeemablePreferredStockMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="us-gaap_MaximumMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MaximumMember_lbl" xml:lang="en-US" id="id_7047976_1275948_1_1">Maximum [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MaximumMember_lbl" xml:lang="en-US" id="id_7047976_1275948_2_1">Maximum [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MaximumMember" xlink:to="us-gaap_MaximumMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_MaximumPeriodOfWarrantsExercisable" xlink:label="cdna_MaximumPeriodOfWarrantsExercisable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_MaximumPeriodOfWarrantsExercisable_lbl" xml:lang="en-US" id="id_7047976_1507578_3_1">Maximum Period Of Warrants Exercisable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_MaximumPeriodOfWarrantsExercisable_lbl" xml:lang="en-US" id="id_7047976_1507578_1_1">Maximum Period Of Warrants Exercisable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_MaximumPeriodOfWarrantsExercisable_lbl" xml:lang="en-US" id="id_7047976_1507578_2_1">Warrants exercisable period</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_MaximumPeriodOfWarrantsExercisable" xlink:to="cdna_MaximumPeriodOfWarrantsExercisable_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_MedicareMember" xlink:label="cdna_MedicareMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_MedicareMember_lbl" xml:lang="en-US" id="id_7047976_1464277_3_1">Medicare [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_MedicareMember_lbl" xml:lang="en-US" id="id_7047976_1464277_1_1">Medicare [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_MedicareMember_lbl" xml:lang="en-US" id="id_7047976_1464277_2_1">Medicare [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_MedicareMember" xlink:to="cdna_MedicareMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MinimumMember" xlink:label="us-gaap_MinimumMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MinimumMember_lbl" xml:lang="en-US" id="id_7047976_1277596_1_1">Minimum [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MinimumMember_lbl" xml:lang="en-US" id="id_7047976_1277596_2_1">Minimum [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MinimumMember" xlink:to="us-gaap_MinimumMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_MinimumSharesOutstandingForVotingRights" xlink:label="cdna_MinimumSharesOutstandingForVotingRights"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_MinimumSharesOutstandingForVotingRights_lbl" xml:lang="en-US" id="id_7047976_1602364_3_1">Minimum shares outstanding for voting rights.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_MinimumSharesOutstandingForVotingRights_lbl" xml:lang="en-US" id="id_7047976_1602364_1_1">Minimum Shares Outstanding For Voting Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_MinimumSharesOutstandingForVotingRights_lbl" xml:lang="en-US" id="id_7047976_1602364_2_1">Minimum number of shares outstanding for voting rights</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_MinimumSharesOutstandingForVotingRights" xlink:to="cdna_MinimumSharesOutstandingForVotingRights_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="us-gaap_NameOfMajorCustomerDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NameOfMajorCustomerDomain_lbl" xml:lang="en-US" id="id_7047976_1280859_1_1">Customer [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NameOfMajorCustomerDomain_lbl" xml:lang="en-US" id="id_7047976_1280859_2_1">Customer [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NameOfMajorCustomerDomain" xlink:to="us-gaap_NameOfMajorCustomerDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1287111_1_1">Net Cash Provided by (Used in) Financing Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1287111_6_1">Net cash provided by (used in) financing activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269355_1_1">Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269355_2_1">Financing activities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1287595_1_1">Net Cash Provided by (Used in) Investing Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1287595_6_1">Net cash (used in) provided by investing activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1277599_1_1">Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1277599_2_1">Investing activities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1272684_1_1">Net Cash Provided by (Used in) Operating Activities, Continuing Operations</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xml:lang="en-US" id="id_7047976_1272684_6_1">Net cash used in operating activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269356_1_1">Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269356_2_1">Operating activities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1284477_1_1">Net Income (Loss) Attributable to Parent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1284477_2_1">Net income (loss)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1284477_6_1">Net income (loss)</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_NetIncomeLoss_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetIncomeLossAbstract" xlink:label="us-gaap_NetIncomeLossAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLossAbstract_lbl" xml:lang="en-US" id="id_7047976_1279253_1_1">Net Income (Loss) Attributable to Parent [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetIncomeLossAbstract_lbl" xml:lang="en-US" id="id_7047976_1279253_2_1">Numerator:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLossAbstract" xlink:to="us-gaap_NetIncomeLossAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xml:lang="en-US" id="id_7047976_1281749_1_1">Net Income (Loss) Available to Common Stockholders, Diluted</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xml:lang="en-US" id="id_7047976_1281749_6_1">Net income (loss) attributable to common stockholders</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279254_1_1">New Accounting Pronouncements, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279254_2_1">Recent Accounting Pronouncement</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1_lbl" xml:lang="en-US" id="id_7047976_1287599_1_1">Noncash or Part Noncash Acquisition, Fixed Assets Acquired</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1_lbl" xml:lang="en-US" id="id_7047976_1287599_2_1">Property and equipment purchased under capital leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1" xlink:to="us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NoninterestExpenseOfferingCost" xlink:label="us-gaap_NoninterestExpenseOfferingCost"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoninterestExpenseOfferingCost_lbl" xml:lang="en-US" id="id_7047976_1286080_1_1">Noninterest Expense Offering Cost</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NoninterestExpenseOfferingCost_lbl" xml:lang="en-US" id="id_7047976_1286080_2_1">Offering expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoninterestExpenseOfferingCost" xlink:to="us-gaap_NoninterestExpenseOfferingCost_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_NonvestedStockOptionsMember" xlink:label="cdna_NonvestedStockOptionsMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_NonvestedStockOptionsMember_lbl" xml:lang="en-US" id="id_7047976_1457274_3_1">Non-vested Stock Options [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_NonvestedStockOptionsMember_lbl" xml:lang="en-US" id="id_7047976_1457274_1_1">Non-vested Stock Options [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_NonvestedStockOptionsMember_lbl" xml:lang="en-US" id="id_7047976_1457274_2_1">Non Vested Stock Options [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_NonvestedStockOptionsMember" xlink:to="cdna_NonvestedStockOptionsMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_NumberOfCommercialTests" xlink:label="cdna_NumberOfCommercialTests"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_NumberOfCommercialTests_lbl" xml:lang="en-US" id="id_7047976_1574491_3_1">Number of Commercial Tests</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_NumberOfCommercialTests_lbl" xml:lang="en-US" id="id_7047976_1574491_1_1">Number of Commercial Tests</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_NumberOfCommercialTests_lbl" xml:lang="en-US" id="id_7047976_1574491_2_1">Number of commercial tests involving the measurement of cfDNA to be completed</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_NumberOfCommercialTests" xlink:to="cdna_NumberOfCommercialTests_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="us-gaap_NumberOfOperatingSegments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US" id="id_7047976_1276002_1_1">Number of Operating Segments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US" id="id_7047976_1276002_2_1">Number of operating segment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfOperatingSegments" xlink:to="us-gaap_NumberOfOperatingSegments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="us-gaap_OperatingExpenses"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingExpenses_lbl" xml:lang="en-US" id="id_7047976_1285548_1_1">Operating Expenses</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingExpenses_lbl" xml:lang="en-US" id="id_7047976_1285548_6_1">Total operating expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingExpenses" xlink:to="us-gaap_OperatingExpenses_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1283121_1_1">Operating Income (Loss)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xml:lang="en-US" id="id_7047976_1283121_6_1">Income (loss) from operations</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingIncomeLoss" xlink:to="us-gaap_OperatingIncomeLoss_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_OperatingLeasesExpirationMonthYear" xlink:label="cdna_OperatingLeasesExpirationMonthYear"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_OperatingLeasesExpirationMonthYear_lbl" xml:lang="en-US" id="id_7047976_1510008_3_1">Operating Leases Expiration Month Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_OperatingLeasesExpirationMonthYear_lbl" xml:lang="en-US" id="id_7047976_1510008_1_1">Operating Leases Expiration Month Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_OperatingLeasesExpirationMonthYear_lbl" xml:lang="en-US" id="id_7047976_1510008_2_1">Operating lease agreement expiry date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_OperatingLeasesExpirationMonthYear" xlink:to="cdna_OperatingLeasesExpirationMonthYear_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_lbl" xml:lang="en-US" id="id_7047976_1283561_1_1">Operating Leases, Future Minimum Payments Due</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_lbl" xml:lang="en-US" id="id_7047976_1283561_6_1">Total minimum lease payments under operating leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_lbl" xml:lang="en-US" id="id_7047976_1284896_1_1">Operating Leases, Future Minimum Payments Due, Next Twelve Months</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_lbl" xml:lang="en-US" id="id_7047976_1284896_2_1">Operating leases, 2015</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_lbl" xml:lang="en-US" id="id_7047976_1283125_1_1">Operating Leases, Future Minimum Payments, Due in Four Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_lbl" xml:lang="en-US" id="id_7047976_1283125_2_1">Operating leases, 2018</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xml:lang="en-US" id="id_7047976_1283564_1_1">Operating Leases, Future Minimum Payments, Due in Three Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xml:lang="en-US" id="id_7047976_1283564_2_1">Operating leases, 2017</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xml:lang="en-US" id="id_7047976_1284469_1_1">Operating Leases, Future Minimum Payments, Due in Two Years</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xml:lang="en-US" id="id_7047976_1284469_2_1">Operating leases, 2016</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_lbl" xml:lang="en-US" id="id_7047976_1282235_1_1">Operating Leases, Future Minimum Payments, Due Thereafter</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_lbl" xml:lang="en-US" id="id_7047976_1282235_2_1">Operating leases, 2019 and thereafter</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:label="us-gaap_OperatingLeasesRentExpenseNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesRentExpenseNet_lbl" xml:lang="en-US" id="id_7047976_1286571_1_1">Operating Leases, Rent Expense, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeasesRentExpenseNet_lbl" xml:lang="en-US" id="id_7047976_1286571_2_1">Rent expense under non-cancelable operating leases</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesRentExpenseNet" xlink:to="us-gaap_OperatingLeasesRentExpenseNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="us-gaap_OperatingLossCarryforwards"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1288124_1_1">Operating Loss Carryforwards</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xml:lang="en-US" id="id_7047976_1288124_2_1">Net operating loss carryforwards</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLossCarryforwards" xlink:to="us-gaap_OperatingLossCarryforwards_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_OperatingLossCarryforwardsExpirationYear" xlink:label="cdna_OperatingLossCarryforwardsExpirationYear"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_OperatingLossCarryforwardsExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1521077_3_1">Operating loss carryforwards expiration year.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_OperatingLossCarryforwardsExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1521077_1_1">Operating Loss Carryforwards Expiration Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_OperatingLossCarryforwardsExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1521077_2_1">Operating loss carryforwards, expiration year</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_OperatingLossCarryforwardsExpirationYear" xlink:to="cdna_OperatingLossCarryforwardsExpirationYear_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OptionIndexedToIssuersEquityTypeAxis" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1272720_1_1">Option Indexed to Issuer's Equity, Type [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1272720_2_1">Option Indexed to Issuer's Equity, Type [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OptionIndexedToIssuersEquityTypeAxis" xlink:to="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OptionIndexedToIssuersEquityTypeDomain" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1276019_1_1">Option Indexed to Issuer's Equity, Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1276019_2_1">Option Indexed to Issuer's Equity, Type [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OptionIndexedToIssuersEquityTypeDomain" xlink:to="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xml:lang="en-US" id="id_7047976_1276020_1_1">Organization, Consolidation and Presentation of Financial Statements [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xml:lang="en-US" id="id_7047976_1276020_2_1">Organization, Consolidation and Presentation of Financial Statements [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1277652_1_1">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1277652_2_1">Organization and Description of Business</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1283556_1_1">Other Accrued Liabilities, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xml:lang="en-US" id="id_7047976_1283556_2_1">Other accrued expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAccruedLiabilitiesCurrent" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1288618_1_1">Other Assets, Noncurrent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1288618_2_1">Other noncurrent assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAssetsNoncurrent" xlink:to="us-gaap_OtherAssetsNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLiabilitiesDisclosureAbstract" xlink:label="us-gaap_OtherLiabilitiesDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilitiesDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1274403_1_1">Other Liabilities Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherLiabilitiesDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1274403_2_1">Other Liabilities Disclosure [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesDisclosureAbstract" xlink:to="us-gaap_OtherLiabilitiesDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1283538_1_1">Other Liabilities, Noncurrent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xml:lang="en-US" id="id_7047976_1283538_2_1">Other Liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesNoncurrent" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherNoncashIncomeTaxExpense" xlink:label="us-gaap_OtherNoncashIncomeTaxExpense"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherNoncashIncomeTaxExpense_lbl" xml:lang="en-US" id="id_7047976_1286595_1_1">Other Noncash Income Tax Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherNoncashIncomeTaxExpense_lbl" xml:lang="en-US" id="id_7047976_1286595_2_1">Non-cash income tax benefit in connection with business combinations</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherNoncashIncomeTaxExpense" xlink:to="us-gaap_OtherNoncashIncomeTaxExpense_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="us-gaap_OtherNonoperatingIncomeExpense"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xml:lang="en-US" id="id_7047976_1284001_1_1">Other Nonoperating Income (Expense)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xml:lang="en-US" id="id_7047976_1284001_2_1">Other income (expense), net</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherNonoperatingIncomeExpense" xlink:to="us-gaap_OtherNonoperatingIncomeExpense_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ParentCompanyMember" xlink:label="us-gaap_ParentCompanyMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ParentCompanyMember_lbl" xml:lang="en-US" id="id_7047976_1271063_1_1">Parent Company [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ParentCompanyMember_lbl" xml:lang="en-US" id="id_7047976_1271063_2_1">CareDx, Inc [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ParentCompanyMember" xlink:to="us-gaap_ParentCompanyMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="us-gaap_PayablesAndAccrualsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269445_1_1">Payables and Accruals [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xml:lang="en-US" id="id_7047976_1269445_2_1">Payables and Accruals [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PayablesAndAccrualsAbstract" xlink:to="us-gaap_PayablesAndAccrualsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsForLegalSettlements" xlink:label="us-gaap_PaymentsForLegalSettlements"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsForLegalSettlements_lbl" xml:lang="en-US" id="id_7047976_1284835_1_1">Payments for Legal Settlements</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PaymentsForLegalSettlements_lbl" xml:lang="en-US" id="id_7047976_1284835_2_1">Settlement and payment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsForLegalSettlements" xlink:to="us-gaap_PaymentsForLegalSettlements_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsForProceedsFromInvestments" xlink:label="us-gaap_PaymentsForProceedsFromInvestments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsForProceedsFromInvestments_lbl" xml:lang="en-US" id="id_7047976_1282190_1_1">Payments for (Proceeds from) Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsForProceedsFromInvestments_lbl" xml:lang="en-US" id="id_7047976_1282190_14_1">Sales of investments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsForProceedsFromInvestments" xlink:to="us-gaap_PaymentsForProceedsFromInvestments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xml:lang="en-US" id="id_7047976_1281683_1_1">Payments of Stock Issuance Costs</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xml:lang="en-US" id="id_7047976_1281683_2_1">Underwriting discounts and commissions</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xml:lang="en-US" id="id_7047976_1281683_14_1">Payment of initial public offering costs</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsOfStockIssuanceCosts" xlink:to="us-gaap_PaymentsOfStockIssuanceCosts_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xml:lang="en-US" id="id_7047976_1283080_1_1">Payments to Acquire Businesses, Net of Cash Acquired</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl" xml:lang="en-US" id="id_7047976_1283080_14_1">Payment for acquisitions, net of cash acquired</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:to="us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireInvestments" xlink:label="us-gaap_PaymentsToAcquireInvestments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xml:lang="en-US" id="id_7047976_1282174_1_1">Payments to Acquire Investments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquireInvestments_lbl" xml:lang="en-US" id="id_7047976_1282174_14_1">Purchase of investments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireInvestments" xlink:to="us-gaap_PaymentsToAcquireInvestments_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US" id="id_7047976_1284434_1_1">Payments to Acquire Property, Plant, and Equipment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US" id="id_7047976_1284434_14_1">Purchase of property and equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279337_1_1">Pension and Other Postretirement Benefits Disclosure [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279337_2_1">401(K) Plan</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock" xlink:to="us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PlanNameAxis_lbl" xml:lang="en-US" id="id_7047976_1280964_1_1">Plan Name [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PlanNameAxis_lbl" xml:lang="en-US" id="id_7047976_1280964_2_1">Plan Name [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PlanNameAxis" xlink:to="us-gaap_PlanNameAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="us-gaap_PlanNameDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PlanNameDomain_lbl" xml:lang="en-US" id="id_7047976_1279330_1_1">Plan Name [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PlanNameDomain_lbl" xml:lang="en-US" id="id_7047976_1279330_2_1">Plan Name [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PlanNameDomain" xlink:to="us-gaap_PlanNameDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_PotentialRefundablePortionOfUpfrontPayment" xlink:label="cdna_PotentialRefundablePortionOfUpfrontPayment"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_PotentialRefundablePortionOfUpfrontPayment_lbl" xml:lang="en-US" id="id_7047976_1465040_3_1">Potential Refundable Portion of Upfront Payment.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_PotentialRefundablePortionOfUpfrontPayment_lbl" xml:lang="en-US" id="id_7047976_1465040_1_1">Potential Refundable Portion of Upfront Payment</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_PotentialRefundablePortionOfUpfrontPayment_lbl" xml:lang="en-US" id="id_7047976_1465040_2_1">Refundable upfront payments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_PotentialRefundablePortionOfUpfrontPayment" xlink:to="cdna_PotentialRefundablePortionOfUpfrontPayment_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockDividendsPerShareDeclared" xlink:label="us-gaap_PreferredStockDividendsPerShareDeclared"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockDividendsPerShareDeclared_lbl" xml:lang="en-US" id="id_7047976_1272803_1_1">Preferred Stock, Dividends Per Share, Declared</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockDividendsPerShareDeclared_lbl" xml:lang="en-US" id="id_7047976_1272803_2_1">Dividend declared per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockDividendsPerShareDeclared" xlink:to="us-gaap_PreferredStockDividendsPerShareDeclared_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="us-gaap_PreferredStockMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1272805_1_1">Preferred Stock [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1272805_2_1">Shares of common stock subject to conversion from preferred stock [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockMember" xlink:to="us-gaap_PreferredStockMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US" id="id_7047976_1280976_1_1">Preferred Stock, Par or Stated Value Per Share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US" id="id_7047976_1280976_2_1">Preferred stock, par value</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockParOrStatedValuePerShare" xlink:to="us-gaap_PreferredStockParOrStatedValuePerShare_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US" id="id_7047976_1279344_1_1">Preferred Stock, Shares Authorized</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US" id="id_7047976_1279344_2_1">Preferred stock, shares authorized</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesAuthorized" xlink:to="us-gaap_PreferredStockSharesAuthorized_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="us-gaap_PreferredStockSharesIssued"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US" id="id_7047976_1280980_1_1">Preferred Stock, Shares Issued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US" id="id_7047976_1280980_2_1">Preferred stock, shares issued</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesIssued" xlink:to="us-gaap_PreferredStockSharesIssued_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="us-gaap_PreferredStockSharesOutstanding"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276106_1_1">Preferred Stock, Shares Outstanding</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276106_2_1">Preferred stock, shares outstanding</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesOutstanding" xlink:to="us-gaap_PreferredStockSharesOutstanding_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockTextBlock" xlink:label="us-gaap_PreferredStockTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276108_1_1">Preferred Stock [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276108_2_1">Convertible Preferred Stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockTextBlock" xlink:to="us-gaap_PreferredStockTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="us-gaap_PreferredStockValue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockValue_lbl" xml:lang="en-US" id="id_7047976_1282154_1_1">Preferred Stock, Value, Issued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockValue_lbl" xml:lang="en-US" id="id_7047976_1282154_2_1">Preferred stock: $0.001 par value; 10,000,000 and 0 shares authorized at December 31, 2014 and December 31, 2013, respectively; 0 and 0 shares issued and outstanding at December 31, 2014 and December 31, 2013, respectively</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockValue" xlink:to="us-gaap_PreferredStockValue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockVotingRights" xlink:label="us-gaap_PreferredStockVotingRights"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockVotingRights_lbl" xml:lang="en-US" id="id_7047976_1271099_1_1">Preferred Stock, Voting Rights</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockVotingRights_lbl" xml:lang="en-US" id="id_7047976_1271099_2_1">Convertible preferred stock voting rights</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockVotingRights" xlink:to="us-gaap_PreferredStockVotingRights_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_PreferredStockWarrantMember" xlink:label="cdna_PreferredStockWarrantMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_PreferredStockWarrantMember_lbl" xml:lang="en-US" id="id_7047976_1319698_3_1">Preferred Stock Warrant [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_PreferredStockWarrantMember_lbl" xml:lang="en-US" id="id_7047976_1319698_1_1">Preferred Stock Warrant [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_PreferredStockWarrantMember_lbl" xml:lang="en-US" id="id_7047976_1319698_2_1">Shares of common stock subject to conversion from preferred stock warrants [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_PreferredStockWarrantMember" xlink:to="cdna_PreferredStockWarrantMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US" id="id_7047976_1286123_1_1">Prepaid Expense and Other Assets, Current</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US" id="id_7047976_1286123_2_1">Prepaid and other assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromDebtNetOfIssuanceCosts" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xml:lang="en-US" id="id_7047976_1287664_1_1">Proceeds from Debt, Net of Issuance Costs</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xml:lang="en-US" id="id_7047976_1287664_2_1">Proceeds from debt, net of issuance costs</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromDebtNetOfIssuanceCosts" xlink:to="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromIssuanceInitialPublicOffering" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1288681_1_1">Proceeds from Issuance Initial Public Offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1288681_2_1">Proceeds from initial public offering net of underwriting discounts and commissions</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xml:lang="en-US" id="id_7047976_1288681_12_1">Proceeds from initial public offering, net of underwriters discount</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceInitialPublicOffering" xlink:to="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromIssuanceOfDebt" xlink:label="us-gaap_ProceedsFromIssuanceOfDebt"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOfDebt_lbl" xml:lang="en-US" id="id_7047976_1285615_1_1">Proceeds from Issuance of Debt</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOfDebt_lbl" xml:lang="en-US" id="id_7047976_1285615_2_1">Net cash proceeds from loan</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOfDebt" xlink:to="us-gaap_ProceedsFromIssuanceOfDebt_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xml:lang="en-US" id="id_7047976_1287189_1_1">Proceeds from Issuance of Redeemable Convertible Preferred Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOfRedeemableConvertiblePreferredStock_lbl" xml:lang="en-US" id="id_7047976_1287189_2_1">Proceeds from issuance of convertible preferred stock, net of issuance costs</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromLicenseFeesReceived" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xml:lang="en-US" id="id_7047976_1287668_1_1">Proceeds from License Fees Received</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromLicenseFeesReceived_lbl" xml:lang="en-US" id="id_7047976_1287668_2_1">Upfront license fee payment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromLicenseFeesReceived" xlink:to="us-gaap_ProceedsFromLicenseFeesReceived_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromSaleAndMaturityOfOtherInvestments" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfOtherInvestments"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfOtherInvestments_lbl" xml:lang="en-US" id="id_7047976_1286657_1_1">Proceeds from Sale and Maturity of Other Investments</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleAndMaturityOfOtherInvestments" xlink:to="us-gaap_ProceedsFromSaleAndMaturityOfOtherInvestments_lbl"/>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromStockOptionsExercised" xlink:to="us-gaap_ProceedsFromStockOptionsExercised_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1276136_1_1">Property, Plant and Equipment, Type [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1276136_2_1">Property, Plant and Equipment, Type [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:to="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" xlink:label="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract_lbl" xml:lang="en-US" id="id_7047976_1580483_3_1">Property Plant And Equipment Capitalized Interest Costs [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract_lbl" xml:lang="en-US" id="id_7047976_1580483_1_1">Property Plant And Equipment Capitalized Interest Costs [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract_lbl" xml:lang="en-US" id="id_7047976_1580483_2_1">Property Plant And Equipment Capitalized Interest Costs [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" xlink:to="cdna_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="us-gaap_PropertyPlantAndEquipmentGross"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xml:lang="en-US" id="id_7047976_1287207_1_1">Property, Plant and Equipment, Gross</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xml:lang="en-US" id="id_7047976_1287207_2_1">Total property and equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentGross" xlink:to="us-gaap_PropertyPlantAndEquipmentGross_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xml:lang="en-US" id="id_7047976_1269502_1_1">Property, Plant and Equipment [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xml:lang="en-US" id="id_7047976_1269502_2_1">Property, Plant and Equipment [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="us-gaap_PropertyPlantAndEquipmentLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentMember" xlink:label="us-gaap_PropertyPlantAndEquipmentMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1279376_1_1">Property, Plant and Equipment [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentMember_lbl" xml:lang="en-US" id="id_7047976_1279376_2_1">Laboratory, Computer, and Office Equipment [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentMember" xlink:to="us-gaap_PropertyPlantAndEquipmentMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US" id="id_7047976_1285626_1_1">Property, Plant and Equipment, Net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US" id="id_7047976_1285626_2_1">Property and equipment, net</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US" id="id_7047976_1285626_6_1">Property and equipment, net</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276143_1_1">Property, Plant and Equipment, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276143_2_1">Property and Equipment, net</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:to="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xml:lang="en-US" id="id_7047976_1281009_1_1">Property, Plant and Equipment [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xml:lang="en-US" id="id_7047976_1281009_2_1">Components of Property and Equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:to="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1274491_1_1">Property, Plant and Equipment, Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1274491_2_1">Property, Plant and Equipment, Type [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:to="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xml:lang="en-US" id="id_7047976_1276144_1_1">Property, Plant and Equipment, Useful Life</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xml:lang="en-US" id="id_7047976_1276144_2_1">Estimated useful lives of assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:to="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_QuarterlyFinancialInformationDisclosureAbstract" xlink:label="us-gaap_QuarterlyFinancialInformationDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_QuarterlyFinancialInformationDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1277772_1_1">Quarterly Financial Information Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_QuarterlyFinancialInformationDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1277772_2_1">Quarterly Financial Information Disclosure [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_QuarterlyFinancialInformationDisclosureAbstract" xlink:to="us-gaap_QuarterlyFinancialInformationDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_QuarterlyFinancialInformationTextBlock" xlink:label="us-gaap_QuarterlyFinancialInformationTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_QuarterlyFinancialInformationTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276165_1_1">Quarterly Financial Information [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_QuarterlyFinancialInformationTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276165_2_1">Selected Quarterly Financial Data</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_QuarterlyFinancialInformationTextBlock" xlink:to="us-gaap_QuarterlyFinancialInformationTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="us-gaap_RangeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RangeAxis_lbl" xml:lang="en-US" id="id_7047976_1269523_1_1">Range [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RangeAxis_lbl" xml:lang="en-US" id="id_7047976_1269523_2_1">Range [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RangeAxis" xlink:to="us-gaap_RangeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="us-gaap_RangeMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RangeMember_lbl" xml:lang="en-US" id="id_7047976_1279402_1_1">Range [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RangeMember_lbl" xml:lang="en-US" id="id_7047976_1279402_2_1">Range [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RangeMember" xlink:to="us-gaap_RangeMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RecognitionOfDeferredRevenue" xlink:label="us-gaap_RecognitionOfDeferredRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RecognitionOfDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1283940_1_1">Recognition of Deferred Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RecognitionOfDeferredRevenue_lbl" xml:lang="en-US" id="id_7047976_1283940_2_1">Revenue recognized from the arrangement</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward" xlink:label="us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_lbl" xml:lang="en-US" id="id_7047976_1279419_1_1">Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ReconciliationOfUnrecognizedTaxBenefitsExcludingAmountsPertainingToExaminedTaxReturnsRollForward_lbl" xml:lang="en-US" id="id_7047976_1279419_2_1">Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ReimbursementRevenue" xlink:label="us-gaap_ReimbursementRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ReimbursementRevenue_lbl" xml:lang="en-US" id="id_7047976_1283930_1_1">Reimbursement Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ReimbursementRevenue_lbl" xml:lang="en-US" id="id_7047976_1283930_2_1">Reimbursement of research and development expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ReimbursementRevenue" xlink:to="us-gaap_ReimbursementRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="us-gaap_RelatedPartyTransactionAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xml:lang="en-US" id="id_7047976_1274544_1_1">Related Party Transaction [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xml:lang="en-US" id="id_7047976_1274544_2_1">Related Party Transaction [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionAxis_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RelatedPartyTransactionDomain_lbl" xml:lang="en-US" id="id_7047976_1281057_1_1">Related Party Transaction [Domain]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xml:lang="en-US" id="id_7047976_1285664_2_1">Research and development</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xml:lang="en-US" id="id_7047976_1285664_12_1">Research and development expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ResearchAndDevelopmentExpense" xlink:to="us-gaap_ResearchAndDevelopmentExpense_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xml:lang="en-US" id="id_7047976_1269570_1_1">Research and Development Expense [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xml:lang="en-US" id="id_7047976_1269570_2_1">Research and Development Expense [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xml:lang="en-US" id="id_7047976_1276218_1_1">Research and Development Expense, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xml:lang="en-US" id="id_7047976_1276218_2_1">Research and Development Expenses</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalents" xlink:label="us-gaap_RestrictedCashAndCashEquivalents"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xml:lang="en-US" id="id_7047976_1286186_1_1">Restricted Cash and Cash Equivalents</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RestrictedCashAndCashEquivalents_lbl" xml:lang="en-US" id="id_7047976_1286186_2_1">Restricted cash</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RestrictedCashAndCashEquivalents" xlink:to="us-gaap_RestrictedCashAndCashEquivalents_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US" id="id_7047976_1283021_1_1">Retained Earnings (Accumulated Deficit)</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US" id="id_7047976_1283021_2_1">Accumulated deficit</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetainedEarningsAccumulatedDeficit" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="us-gaap_RetainedEarningsMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US" id="id_7047976_1269588_1_1">Retained Earnings [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US" id="id_7047976_1269588_2_1">Accumulated Deficit [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetainedEarningsMember" xlink:to="us-gaap_RetainedEarningsMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized" xlink:label="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_lbl" xml:lang="en-US" id="id_7047976_1282115_1_1">Revenue Recognition, Milestone Method, Revenue Recognized</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_lbl" xml:lang="en-US" id="id_7047976_1282115_2_1">Revenue recognition under milestone method</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized" xlink:to="us-gaap_RevenueRecognitionMilestoneMethodRevenueRecognized_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RevenueRecognitionMultipleElementArrangements" xlink:label="us-gaap_RevenueRecognitionMultipleElementArrangements"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RevenueRecognitionMultipleElementArrangements_lbl" xml:lang="en-US" id="id_7047976_1269595_1_1">Revenue Recognition, Multiple-deliverable Arrangements, Description [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RevenueRecognitionMultipleElementArrangements_lbl" xml:lang="en-US" id="id_7047976_1269595_2_1">Collaboration and License Revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueRecognitionMultipleElementArrangements" xlink:to="us-gaap_RevenueRecognitionMultipleElementArrangements_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1272964_1_1">Revenue Recognition, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1272964_2_1">Testing Revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueRecognitionPolicyTextBlock" xlink:to="us-gaap_RevenueRecognitionPolicyTextBlock_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Revenues_lbl" xml:lang="en-US" id="id_7047976_1284373_1_1">Revenues</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_Revenues_lbl" xml:lang="en-US" id="id_7047976_1284373_2_1">Total revenue</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RevenuesAbstract" xlink:label="us-gaap_RevenuesAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RevenuesAbstract_lbl" xml:lang="en-US" id="id_7047976_1271283_1_1">Revenues [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RevenuesAbstract_lbl" xml:lang="en-US" id="id_7047976_1271283_2_1">Revenue:</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_RoyaltyAgreementLiabilityMember" xlink:label="cdna_RoyaltyAgreementLiabilityMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_RoyaltyAgreementLiabilityMember_lbl" xml:lang="en-US" id="id_7047976_1455925_3_1">Royalty Agreement Liability [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_RoyaltyAgreementLiabilityMember_lbl" xml:lang="en-US" id="id_7047976_1455925_1_1">Royalty Agreement Liability [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_RoyaltyAgreementLiabilityMember_lbl" xml:lang="en-US" id="id_7047976_1455925_2_1">Unpaid Royalties [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RoyaltyExpense_lbl" xml:lang="en-US" id="id_7047976_1287246_1_1">Royalty Expense</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RoyaltyExpense_lbl" xml:lang="en-US" id="id_7047976_1287246_2_1">Royalty expenses</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RoyaltyRevenue" xlink:label="us-gaap_RoyaltyRevenue"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RoyaltyRevenue_lbl" xml:lang="en-US" id="id_7047976_1283914_1_1">Royalty Revenue</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RoyaltyRevenue_lbl" xml:lang="en-US" id="id_7047976_1283914_2_1">Royalty revenues</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RoyaltyRevenue" xlink:to="us-gaap_RoyaltyRevenue_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_RoyaltyRevenueReceivable" xlink:label="cdna_RoyaltyRevenueReceivable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_RoyaltyRevenueReceivable_lbl" xml:lang="en-US" id="id_7047976_1574624_3_1">Royalty Revenue Receivable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_RoyaltyRevenueReceivable_lbl" xml:lang="en-US" id="id_7047976_1574624_1_1">Royalty Revenue Receivable</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_RoyaltyRevenueReceivable_lbl" xml:lang="en-US" id="id_7047976_1574624_2_1">Royalty revenues receivable balance</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_RoyaltyRevenueReceivable" xlink:to="cdna_RoyaltyRevenueReceivable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xml:lang="en-US" id="id_7047976_1288739_1_1">Sale of Stock, Consideration Received on Transaction</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xml:lang="en-US" id="id_7047976_1288739_2_1">Net proceeds from issuance of initial public offering</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xml:lang="en-US" id="id_7047976_1288739_12_1">Shares sold for consideration</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:to="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xml:lang="en-US" id="id_7047976_1279494_1_1">Sale of Stock [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xml:lang="en-US" id="id_7047976_1279494_2_1">Sale of Stock [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="us-gaap_SaleOfStockPricePerShare"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xml:lang="en-US" id="id_7047976_1281096_1_1">Sale of Stock, Price Per Share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SaleOfStockPricePerShare_lbl" xml:lang="en-US" id="id_7047976_1281096_2_1">Public offering price per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockPricePerShare" xlink:to="us-gaap_SaleOfStockPricePerShare_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption" xlink:label="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption_lbl" xml:lang="en-US" id="id_7047976_1421197_3_1">Sale of stock pursuant to exercise of underwriters over allotment option.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption_lbl" xml:lang="en-US" id="id_7047976_1421197_1_1">Sale Of Stock Pursuant To Exercise Of Underwriters Over Allotment Option</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption_lbl" xml:lang="en-US" id="id_7047976_1421197_2_1">Issuance of additional shares pursuant to exercise of underwriters' overallotment option</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption" xlink:to="cdna_SaleOfStockPursuantToExerciseOfUnderwritersOverAllotmentOption_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SalesRevenueServicesNet" xlink:label="us-gaap_SalesRevenueServicesNet"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SeriesBConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1493912_1_1">Series B Convertible Preferred Stock [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SeriesBConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1493912_2_1">Series B Convertible Preferred Stock [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SeriesCConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1559024_2_1">Series C Convertible Preferred Stock [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SeriesDConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1343554_2_1">Series D Convertible Preferred Stock [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SeriesDPreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1281158_2_1">Series D Preferred Stock [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SeriesEConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1334003_1_1">Series E Convertible Preferred Stock [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SeriesEConvertiblePreferredStockMember_lbl" xml:lang="en-US" id="id_7047976_1334003_2_1">Series E Convertible Preferred Stock [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantAssumedInAcquisition_lbl" xml:lang="en-US" id="id_7047976_1345314_1_1">Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant Assumed In Acquisition</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesAcquisitions_lbl" xml:lang="en-US" id="id_7047976_1271369_2_1">Convertible preferred stock Series G issued for the acquisition of ImmuMetrix, Inc., Shares</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_StockIssuedDuringPeriodSharesConversionOfPreferredStockToCommonStock_lbl" xml:lang="en-US" id="id_7047976_1414178_3_1">Stock Issued During Period Shares Conversion Of Preferred Stock To Common Stock</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfUnits_lbl" xml:lang="en-US" id="id_7047976_1271370_1_1">Stock Issued During Period, Shares, Conversion of Units</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" xml:lang="en-US" id="id_7047976_1278012_1_1">Stock Issued During Period, Shares, Issued for Services</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesIssuedForServices_lbl" xml:lang="en-US" id="id_7047976_1278012_2_1">Issuance of common stock for services, Shares</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US" id="id_7047976_1274739_1_1">Stock Issued During Period, Shares, New Issues</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US" id="id_7047976_1274739_2_1">Common stock shares issued from IPO</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xml:lang="en-US" id="id_7047976_1281224_14_1">Number of Shares, Exercised</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions_lbl" xml:lang="en-US" id="id_7047976_1282998_2_1">Convertible preferred stock Series G issued for the acquisition of ImmuMetrix, Inc.</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xml:lang="en-US" id="id_7047976_1284348_1_1">Stock Issued During Period, Value, Conversion of Convertible Securities</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xml:lang="en-US" id="id_7047976_1284348_2_1">Convertible note principal amount</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesNetOfAdjustments_lbl" xml:lang="en-US" id="id_7047976_1281590_1_1">Stock Issued During Period, Value, Conversion of Convertible Securities, Net of Adjustments</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesNetOfAdjustments_lbl" xml:lang="en-US" id="id_7047976_1281590_2_1">Conversion of notes payable and interest in April 2012 to Series G convertible preferred stock, net of issuance costs</label>
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    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_StockIssuedDuringPeriodValueConversionOfPreferredStockToCommonStock" xlink:label="cdna_StockIssuedDuringPeriodValueConversionOfPreferredStockToCommonStock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_StockIssuedDuringPeriodValueConversionOfPreferredStockToCommonStock_lbl" xml:lang="en-US" id="id_7047976_1373302_3_1">Stock Issued During Period Value Conversion Of Preferred Stock To Common Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_StockIssuedDuringPeriodValueConversionOfPreferredStockToCommonStock_lbl" xml:lang="en-US" id="id_7047976_1373302_1_1">Stock Issued During Period Value Conversion Of Preferred Stock To Common Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_StockIssuedDuringPeriodValueConversionOfPreferredStockToCommonStock_lbl" xml:lang="en-US" id="id_7047976_1373302_2_1">Issuance of Series G convertible preferred stock in April 2012 for cash, net of issuance costs</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xml:lang="en-US" id="id_7047976_1281591_1_1">Stock Issued During Period, Value, Conversion of Units</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits_lbl" xml:lang="en-US" id="id_7047976_1281591_2_1">Conversion of convertible preferred stock to common stock upon initial public offering</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_lbl" xml:lang="en-US" id="id_7047976_1284740_1_1">Stock Issued During Period, Value, Issued for Services</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_lbl" xml:lang="en-US" id="id_7047976_1284740_2_1">Issuance of common stock for services</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueIssuedForServices" xlink:to="us-gaap_StockIssuedDuringPeriodValueIssuedForServices_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xml:lang="en-US" id="id_7047976_1281592_1_1">Stock Issued During Period, Value, New Issues</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xml:lang="en-US" id="id_7047976_1281592_2_1">Conversion of subordinated convertible note to common stock upon initial public offering</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xml:lang="en-US" id="id_7047976_1283001_1_1">Stock Issued During Period, Value, Stock Options Exercised</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xml:lang="en-US" id="id_7047976_1283001_2_1">Issuance of common stock for cash upon exercise of stock options</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:to="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockOptionMember" xlink:label="us-gaap_StockOptionMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockOptionMember_lbl" xml:lang="en-US" id="id_7047976_1281225_1_1">Equity Option [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockOptionMember_lbl" xml:lang="en-US" id="id_7047976_1281225_2_1">Shares of common stock subject to outstanding options [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockOptionMember" xlink:to="us-gaap_StockOptionMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_SubordinatedConvertiblePromissoryNotesMember" xlink:label="cdna_SubordinatedConvertiblePromissoryNotesMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_SubordinatedConvertiblePromissoryNotesMember_lbl" xml:lang="en-US" id="id_7047976_1350952_3_1">Subordinated Convertible Promissory Notes [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SubordinatedConvertiblePromissoryNotesMember_lbl" xml:lang="en-US" id="id_7047976_1350952_1_1">Subordinated Convertible Promissory Notes [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SubordinatedConvertiblePromissoryNotesMember_lbl" xml:lang="en-US" id="id_7047976_1350952_2_1">Subordinated Convertible Promissory Notes [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_SubordinatedConvertiblePromissoryNotesMember" xlink:to="cdna_SubordinatedConvertiblePromissoryNotesMember_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xml:lang="en-US" id="id_7047976_1269753_1_1">Subsequent Event [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventLineItems_lbl" xml:lang="en-US" id="id_7047976_1269753_2_1">Subsequent Event [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_SubsequentEventLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="us-gaap_SubsequentEventMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventMember_lbl" xml:lang="en-US" id="id_7047976_1273350_1_1">Subsequent Event [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventMember_lbl" xml:lang="en-US" id="id_7047976_1273350_2_1">Subsequent Event [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventMember" xlink:to="us-gaap_SubsequentEventMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="us-gaap_SubsequentEventsAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xml:lang="en-US" id="id_7047976_1279606_1_1">Subsequent Events [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xml:lang="en-US" id="id_7047976_1279606_2_1">Subsequent Events [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventsAbstract" xlink:to="us-gaap_SubsequentEventsAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="us-gaap_SubsequentEventsTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US" id="id_7047976_1278000_1_1">Subsequent Events [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US" id="id_7047976_1278000_2_1">Subsequent Event</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventsTextBlock" xlink:to="us-gaap_SubsequentEventsTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="us-gaap_SubsequentEventTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventTable_lbl" xml:lang="en-US" id="id_7047976_1273352_1_1">Subsequent Event [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventTable_lbl" xml:lang="en-US" id="id_7047976_1273352_2_1">Subsequent Event [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventTable" xlink:to="us-gaap_SubsequentEventTable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="us-gaap_SubsequentEventTypeAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1271378_1_1">Subsequent Event Type [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xml:lang="en-US" id="id_7047976_1271378_2_1">Subsequent Event Type [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventTypeAxis" xlink:to="us-gaap_SubsequentEventTypeAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="us-gaap_SubsequentEventTypeDomain"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1276407_1_1">Subsequent Event Type [Domain]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xml:lang="en-US" id="id_7047976_1276407_2_1">Subsequent Event Type [Domain]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventTypeDomain" xlink:to="us-gaap_SubsequentEventTypeDomain_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_lbl" xml:lang="en-US" id="id_7047976_1281233_1_1">Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_lbl" xml:lang="en-US" id="id_7047976_1281233_2_1">Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:to="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xml:lang="en-US" id="id_7047976_1271382_1_1">Sale of Stock [Axis]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xml:lang="en-US" id="id_7047976_1271382_2_1">Sale of Stock [Axis]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_SummaryActivityInGoldBullionLineItems" xlink:label="cdna_SummaryActivityInGoldBullionLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_SummaryActivityInGoldBullionLineItems_lbl" xml:lang="en-US" id="id_7047976_1356414_3_1">Summary Activity In Gold Bullion [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SummaryActivityInGoldBullionLineItems_lbl" xml:lang="en-US" id="id_7047976_1356414_1_1">Summary Activity In Gold Bullion [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SummaryActivityInGoldBullionLineItems_lbl" xml:lang="en-US" id="id_7047976_1356414_2_1">Summary Activity In Gold Bullion [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_SummaryActivityInGoldBullionLineItems" xlink:to="cdna_SummaryActivityInGoldBullionLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SummaryOfIncomeTaxContingenciesTextBlock" xlink:label="us-gaap_SummaryOfIncomeTaxContingenciesTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SummaryOfIncomeTaxContingenciesTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276410_1_1">Summary of Income Tax Contingencies [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SummaryOfIncomeTaxContingenciesTextBlock_lbl" xml:lang="en-US" id="id_7047976_1276410_2_1">Schedule of Reconciliation of Unrecognized Tax Benefits</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SummaryOfIncomeTaxContingenciesTextBlock" xlink:to="us-gaap_SummaryOfIncomeTaxContingenciesTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_SummaryOfSignificantAccountingPoliciesLineItems" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xml:lang="en-US" id="id_7047976_1556063_3_1">Summary Of Significant Accounting Policies [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xml:lang="en-US" id="id_7047976_1556063_1_1">Summary Of Significant Accounting Policies [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesLineItems_lbl" xml:lang="en-US" id="id_7047976_1556063_2_1">Summary Of Significant Accounting Policies [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="cdna_SummaryOfSignificantAccountingPoliciesLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_SummaryOfSignificantAccountingPoliciesTable" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesTable"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesTable_lbl" xml:lang="en-US" id="id_7047976_1394184_3_1">Summary Of Significant Accounting Policies [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesTable_lbl" xml:lang="en-US" id="id_7047976_1394184_1_1">Summary Of Significant Accounting Policies [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_SummaryOfSignificantAccountingPoliciesTable_lbl" xml:lang="en-US" id="id_7047976_1394184_2_1">Summary Of Significant Accounting Policies [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_SummaryOfSignificantAccountingPoliciesTable" xlink:to="cdna_SummaryOfSignificantAccountingPoliciesTable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SupplementalBalanceSheetDisclosuresTextBlock" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl" xml:lang="en-US" id="id_7047976_1278021_1_1">Supplemental Balance Sheet Disclosures [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl" xml:lang="en-US" id="id_7047976_1278021_2_1">Balance Sheet Components</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock" xlink:to="us-gaap_SupplementalBalanceSheetDisclosuresTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xml:lang="en-US" id="id_7047976_1271385_1_1">Supplemental Cash Flow Information [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xml:lang="en-US" id="id_7047976_1271385_2_1">Supplemental disclosures of cash information</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SupplementalCashFlowInformationAbstract" xlink:to="us-gaap_SupplementalCashFlowInformationAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount" xlink:label="us-gaap_TaxCreditCarryforwardAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TaxCreditCarryforwardAmount_lbl" xml:lang="en-US" id="id_7047976_1288257_1_1">Tax Credit Carryforward, Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TaxCreditCarryforwardAmount_lbl" xml:lang="en-US" id="id_7047976_1288257_2_1">Tax credit carryforwards</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TaxCreditCarryforwardAmount" xlink:to="us-gaap_TaxCreditCarryforwardAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TaxCreditCarryForwardExpirationYear" xlink:label="cdna_TaxCreditCarryForwardExpirationYear"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TaxCreditCarryForwardExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1374493_3_1">Tax credit carryforward expiration year.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TaxCreditCarryForwardExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1374493_1_1">Tax Credit Carry Forward Expiration Year</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TaxCreditCarryForwardExpirationYear_lbl" xml:lang="en-US" id="id_7047976_1374493_2_1">Tax credit carryforwards, expiration year</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TaxCreditCarryForwardExpirationYear" xlink:to="cdna_TaxCreditCarryForwardExpirationYear_lbl"/>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xml:lang="en-US" id="id_7047976_1273371_1_1">Temporary Equity, by Class of Stock [Table]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityByClassOfStockTable_lbl" xml:lang="en-US" id="id_7047976_1273371_2_1">Temporary Equity, by Class of Stock [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityByClassOfStockTable" xlink:to="us-gaap_TemporaryEquityByClassOfStockTable_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US" id="id_7047976_1281582_1_1">Temporary Equity, Carrying Amount, Attributable to Parent</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US" id="id_7047976_1281582_2_1">Carrying Value</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US" id="id_7047976_1281582_12_1">Convertible preferred stock: $0.001 par value; 0 and 6,417,954 shares authorized at December 31, 2014 and 2013, respectively; 0 and 5,155,673 shares issued and outstanding at December 31, 2014 and 2013, respectively; liquidation value of $0 and $137,221 at December 31, 2014 and 2013, respectively</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityDisclosureAbstract" xlink:label="us-gaap_TemporaryEquityDisclosureAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1281251_1_1">Temporary Equity Disclosure [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityDisclosureAbstract_lbl" xml:lang="en-US" id="id_7047976_1281251_2_1">Temporary Equity Disclosure [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityDisclosureAbstract" xlink:to="us-gaap_TemporaryEquityDisclosureAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TemporaryEquityInitialConversionPrice" xlink:label="cdna_TemporaryEquityInitialConversionPrice"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TemporaryEquityInitialConversionPrice_lbl" xml:lang="en-US" id="id_7047976_1482357_3_1">Temporary equity initial conversion price.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TemporaryEquityInitialConversionPrice_lbl" xml:lang="en-US" id="id_7047976_1482357_1_1">Temporary Equity Initial Conversion Price</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TemporaryEquityInitialConversionPrice_lbl" xml:lang="en-US" id="id_7047976_1482357_2_1">Initial conversion price per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TemporaryEquityInitialConversionPrice" xlink:to="cdna_TemporaryEquityInitialConversionPrice_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityLineItems" xlink:label="us-gaap_TemporaryEquityLineItems"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xml:lang="en-US" id="id_7047976_1274772_1_1">Temporary Equity [Line Items]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityLineItems_lbl" xml:lang="en-US" id="id_7047976_1274772_2_1">Temporary Equity [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityLineItems" xlink:to="us-gaap_TemporaryEquityLineItems_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityLiquidationPreference" xlink:label="us-gaap_TemporaryEquityLiquidationPreference"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xml:lang="en-US" id="id_7047976_1282068_1_1">Temporary Equity, Liquidation Preference</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xml:lang="en-US" id="id_7047976_1282068_2_1">Convertible preferred stock, liquidation</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TemporaryEquityLiquidationPreference_lbl" xml:lang="en-US" id="id_7047976_1282068_12_1">Liquidation Value</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityLiquidationPreference" xlink:to="us-gaap_TemporaryEquityLiquidationPreference_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityLiquidationPreferencePerShare" xlink:label="us-gaap_TemporaryEquityLiquidationPreferencePerShare"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityLiquidationPreferencePerShare_lbl" xml:lang="en-US" id="id_7047976_1269774_1_1">Temporary Equity, Liquidation Preference Per Share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityLiquidationPreferencePerShare_lbl" xml:lang="en-US" id="id_7047976_1269774_2_1">Liquidation preferences per share</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityLiquidationPreferencePerShare" xlink:to="us-gaap_TemporaryEquityLiquidationPreferencePerShare_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:label="us-gaap_TemporaryEquityParOrStatedValuePerShare"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityParOrStatedValuePerShare_lbl" xml:lang="en-US" id="id_7047976_1279887_1_1">Temporary Equity, Par or Stated Value Per Share</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityParOrStatedValuePerShare_lbl" xml:lang="en-US" id="id_7047976_1279887_2_1">Convertible preferred stock, par value</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:to="us-gaap_TemporaryEquityParOrStatedValuePerShare_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquitySharesAuthorized" xlink:label="us-gaap_TemporaryEquitySharesAuthorized"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xml:lang="en-US" id="id_7047976_1278320_1_1">Temporary Equity, Shares Authorized</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xml:lang="en-US" id="id_7047976_1278320_2_1">Convertible preferred stock, shares authorized</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xml:lang="en-US" id="id_7047976_1278320_12_1">Shares Authorized</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesAuthorized" xlink:to="us-gaap_TemporaryEquitySharesAuthorized_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquitySharesIssued" xlink:label="us-gaap_TemporaryEquitySharesIssued"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xml:lang="en-US" id="id_7047976_1271406_1_1">Temporary Equity, Shares Issued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xml:lang="en-US" id="id_7047976_1271406_2_1">Convertible preferred stock, shares issued</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesIssued" xlink:to="us-gaap_TemporaryEquitySharesIssued_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquitySharesOutstanding" xlink:label="us-gaap_TemporaryEquitySharesOutstanding"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1278321_1_1">Temporary Equity, Shares Outstanding</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1278321_2_1">Convertible preferred stock, shares outstanding</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1278321_12_1">Shares Outstanding</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesOutstanding" xlink:to="us-gaap_TemporaryEquitySharesOutstanding_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TemporaryEquityTableTextBlock" xlink:label="us-gaap_TemporaryEquityTableTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityTableTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279888_1_1">Temporary Equity [Table Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityTableTextBlock_lbl" xml:lang="en-US" id="id_7047976_1279888_2_1">Schedule of Convertible Preferred Stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityTableTextBlock" xlink:to="us-gaap_TemporaryEquityTableTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TerminationAgreementDate" xlink:label="cdna_TerminationAgreementDate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TerminationAgreementDate_lbl" xml:lang="en-US" id="id_7047976_1394864_3_1">Termination agreement date.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TerminationAgreementDate_lbl" xml:lang="en-US" id="id_7047976_1394864_1_1">Termination Agreement Date</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TerminationAgreementDate_lbl" xml:lang="en-US" id="id_7047976_1394864_2_1">Termination of collaboration agreement date</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TerminationAgreementDate" xlink:to="cdna_TerminationAgreementDate_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TerminationFee" xlink:label="cdna_TerminationFee"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TerminationFee_lbl" xml:lang="en-US" id="id_7047976_1414031_3_1">Termination fee.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TerminationFee_lbl" xml:lang="en-US" id="id_7047976_1414031_1_1">Termination Fee</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TerminationFee_lbl" xml:lang="en-US" id="id_7047976_1414031_2_1">Termination agreement fee</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TerminationFee" xlink:to="cdna_TerminationFee_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TextBlockAbstract" xlink:label="us-gaap_TextBlockAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TextBlockAbstract_lbl" xml:lang="en-US" id="id_7047976_1276429_1_1">Text Block [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TextBlockAbstract_lbl" xml:lang="en-US" id="id_7047976_1276429_2_1">Text Block [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TextBlockAbstract" xlink:to="us-gaap_TextBlockAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_TradingSymbol" xlink:label="dei_TradingSymbol"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_TradingSymbol_lbl" xml:lang="en-US" id="id_7047976_1269880_1_1">Trading Symbol</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="dei_TradingSymbol_lbl" xml:lang="en-US" id="id_7047976_1269880_2_1">Trading Symbol</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_TradingSymbol" xlink:to="dei_TradingSymbol_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TrancheATermLoanFacilityMember" xlink:label="cdna_TrancheATermLoanFacilityMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TrancheATermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1296890_3_1">Tranche A Term Loan Facility [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TrancheATermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1296890_1_1">Tranche A Term Loan Facility [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TrancheATermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1296890_2_1">Draw A [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TrancheATermLoanFacilityMember" xlink:to="cdna_TrancheATermLoanFacilityMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TrancheBTermLoanFacilityMember" xlink:label="cdna_TrancheBTermLoanFacilityMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TrancheBTermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1531486_3_1">Tranche B Term Loan Facility [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TrancheBTermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1531486_1_1">Tranche B Term Loan Facility [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TrancheBTermLoanFacilityMember_lbl" xml:lang="en-US" id="id_7047976_1531486_2_1">Draw B [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TrancheBTermLoanFacilityMember" xlink:to="cdna_TrancheBTermLoanFacilityMember_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TransfersAndServicingAbstract" xlink:label="us-gaap_TransfersAndServicingAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TransfersAndServicingAbstract_lbl" xml:lang="en-US" id="id_7047976_1279915_1_1">Transfers and Servicing [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TransfersAndServicingAbstract_lbl" xml:lang="en-US" id="id_7047976_1279915_2_1">Transfers and Servicing [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TransfersAndServicingAbstract" xlink:to="us-gaap_TransfersAndServicingAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TwoThousandAndFourteenEquityIncentivePlanMember" xlink:label="cdna_TwoThousandAndFourteenEquityIncentivePlanMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TwoThousandAndFourteenEquityIncentivePlanMember_lbl" xml:lang="en-US" id="id_7047976_1328523_3_1">Two Thousand And Fourteen Equity Incentive Plan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TwoThousandAndFourteenEquityIncentivePlanMember_lbl" xml:lang="en-US" id="id_7047976_1328523_1_1">Two Thousand And Fourteen Equity Incentive Plan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TwoThousandAndFourteenEquityIncentivePlanMember_lbl" xml:lang="en-US" id="id_7047976_1328523_2_1">2014 Equity Incentive Plan [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_TwoThousandAndFourteenEquityIncentivePlanMember" xlink:to="cdna_TwoThousandAndFourteenEquityIncentivePlanMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_TwoThousandAndTenTermLoanMember" xlink:label="cdna_TwoThousandAndTenTermLoanMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TwoThousandAndTenTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1502108_3_1">Two Thousand And Ten Term Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TwoThousandAndTenTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1502108_1_1">Two Thousand And Ten Term Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TwoThousandAndTenTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1502108_2_1">2010 Loan [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_TwoThousandTwelveTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1432615_3_1">Two Thousand Twelve Term Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_TwoThousandTwelveTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1432615_1_1">Two Thousand Twelve Term Loan [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_TwoThousandTwelveTermLoanMember_lbl" xml:lang="en-US" id="id_7047976_1432615_2_1">2012 Loan [Member]</label>
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    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xml:lang="en-US" id="id_7047976_1284730_1_1">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xml:lang="en-US" id="id_7047976_1284730_2_1">Accrued interest and penalties related to unrecognized tax benefits</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:to="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions" xlink:label="cdna_UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions_lbl" xml:lang="en-US" id="id_7047976_1466653_3_1">Unrecognized tax benefits increase decrease resulting from prior period tax positions.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions_lbl" xml:lang="en-US" id="id_7047976_1466653_1_1">Unrecognized Tax Benefits Increase Decrease Resulting From Prior Period Tax Positions</label>
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    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xml:lang="en-US" id="id_7047976_1283872_1_1">Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl" xml:lang="en-US" id="id_7047976_1283872_2_1">Additions based on tax positions related to current year</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:to="us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xml:lang="en-US" id="id_7047976_1282545_1_1">Unrecognized Tax Benefits that Would Impact Effective Tax Rate</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl" xml:lang="en-US" id="id_7047976_1282545_2_1">Unrecognized tax benefits would impact the income tax provision</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate" xlink:to="us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UpFrontPaymentArrangementMember" xlink:label="us-gaap_UpFrontPaymentArrangementMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UpFrontPaymentArrangementMember_lbl" xml:lang="en-US" id="id_7047976_1273416_1_1">Up-front Payment Arrangement [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UpFrontPaymentArrangementMember_lbl" xml:lang="en-US" id="id_7047976_1273416_2_1">Up-front Payment Arrangement [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UpFrontPaymentArrangementMember" xlink:to="us-gaap_UpFrontPaymentArrangementMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_UpfrontPaymentInCash" xlink:label="cdna_UpfrontPaymentInCash"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_UpfrontPaymentInCash_lbl" xml:lang="en-US" id="id_7047976_1338085_3_1">Upfront Payment In Cash</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_UpfrontPaymentInCash_lbl" xml:lang="en-US" id="id_7047976_1338085_1_1">Upfront Payment In Cash</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_UpfrontPaymentInCash_lbl" xml:lang="en-US" id="id_7047976_1338085_2_1">Upfront cash payment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_UpfrontPaymentInCash" xlink:to="cdna_UpfrontPaymentInCash_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="us-gaap_UseOfEstimates"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UseOfEstimates_lbl" xml:lang="en-US" id="id_7047976_1274809_1_1">Use of Estimates, Policy [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_UseOfEstimates_lbl" xml:lang="en-US" id="id_7047976_1274809_2_1">Use of Estimates</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UseOfEstimates" xlink:to="us-gaap_UseOfEstimates_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xml:lang="en-US" id="id_7047976_1282061_1_1">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl" xml:lang="en-US" id="id_7047976_1282061_14_1">Decrease in valuation allowance</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:to="us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WarrantMember" xlink:label="us-gaap_WarrantMember"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantMember_lbl" xml:lang="en-US" id="id_7047976_1273442_1_1">Warrant [Member]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantMember_lbl" xml:lang="en-US" id="id_7047976_1273442_2_1">Shares of common stock subject to outstanding warrants [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantMember" xlink:to="us-gaap_WarrantMember_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_WarrantPolicyTextBlock" xlink:label="cdna_WarrantPolicyTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_WarrantPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1539126_3_1">Disclosure of accounting policy for recognizing and measuring the fair value of warrants accounted for as a liability.</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_WarrantPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1539126_1_1">Warrant [Policy Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_WarrantPolicyTextBlock_lbl" xml:lang="en-US" id="id_7047976_1539126_2_1">Warrants</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_WarrantPolicyTextBlock" xlink:to="cdna_WarrantPolicyTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_WarrantsDisclosureTextBlock" xlink:label="cdna_WarrantsDisclosureTextBlock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_WarrantsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1531406_3_1">Warrants Disclosure [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_WarrantsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1531406_1_1">Warrants Disclosure [Text Block]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_WarrantsDisclosureTextBlock_lbl" xml:lang="en-US" id="id_7047976_1531406_2_1">Warrants</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_WarrantsDisclosureTextBlock" xlink:to="cdna_WarrantsDisclosureTextBlock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WarrantsNotSettleableInCashFairValueDisclosure" xlink:label="us-gaap_WarrantsNotSettleableInCashFairValueDisclosure"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantsNotSettleableInCashFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1284312_1_1">Warrants Not Settleable in Cash, Fair Value Disclosure</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantsNotSettleableInCashFairValueDisclosure_lbl" xml:lang="en-US" id="id_7047976_1284312_2_1">Estimated Fair Value as of December 31, 2013</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantsNotSettleableInCashFairValueDisclosure" xlink:to="us-gaap_WarrantsNotSettleableInCashFairValueDisclosure_lbl"/>
    <loc xlink:type="locator" xlink:href="cdna-20141231.xsd#cdna_WarrantsToPurchaseConvertiblePreferredStock" xlink:label="cdna_WarrantsToPurchaseConvertiblePreferredStock"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="cdna_WarrantsToPurchaseConvertiblePreferredStock_lbl" xml:lang="en-US" id="id_7047976_1454872_3_1">Warrants To Purchase Convertible Preferred Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="cdna_WarrantsToPurchaseConvertiblePreferredStock_lbl" xml:lang="en-US" id="id_7047976_1454872_1_1">Warrants To Purchase Convertible Preferred Stock</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="cdna_WarrantsToPurchaseConvertiblePreferredStock_lbl" xml:lang="en-US" id="id_7047976_1454872_2_1">Warrants to purchase convertible preferred stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="cdna_WarrantsToPurchaseConvertiblePreferredStock" xlink:to="cdna_WarrantsToPurchaseConvertiblePreferredStock_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl" xml:lang="en-US" id="id_7047976_1279615_1_1">Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl" xml:lang="en-US" id="id_7047976_1279615_2_1">Effect of potentially dilutive securities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" xlink:to="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276710_1_1">Weighted Average Number of Shares Outstanding, Diluted</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276710_2_1">Diluted</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276710_6_1">Weighted-average shares used to compute diluted net income (loss) per share attributable to common stockholders</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US" id="id_7047976_1276710_12_1">Shares used in calculation of net income (loss) per share, diluted</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_lbl" xml:lang="en-US" id="id_7047976_1274823_1_1">Weighted Average Number of Shares Outstanding, Basic and Diluted</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_lbl" xml:lang="en-US" id="id_7047976_1274823_2_1">Shares used in calculation of net loss per share, basic and diluted</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:to="us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract"/>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xml:lang="en-US" id="id_7047976_1274824_1_1">Weighted Average Number of Shares Outstanding, Diluted [Abstract]</label>
    <label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xml:lang="en-US" id="id_7047976_1274824_2_1">Shares used to compute net income (loss) per share:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
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