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  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_EquitySecuritiesFVNIAccumulatedGrossUnrealizedGainLossBeforeTax" abstract="false" name="EquitySecuritiesFVNIAccumulatedGrossUnrealizedGainLossBeforeTax" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_WarrantsDisclosureTextBlock" abstract="false" name="WarrantsDisclosureTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cdna_IntangibleAssetMeasurementInputDiscountRate" abstract="false" name="IntangibleAssetMeasurementInputDiscountRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="cdna_MiromatrixIncMember" abstract="true" name="MiromatrixIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_ScheduleOfShareBasedCompensationStockOptionsAndUnvestedRestrictedStockUnitsActivityTableTableTextBlock" abstract="false" name="ScheduleOfShareBasedCompensationStockOptionsAndUnvestedRestrictedStockUnitsActivityTableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cdna_MarketableSecuritiesAmortizedCostLongTerm" abstract="false" name="MarketableSecuritiesAmortizedCostLongTerm" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_UnsubmittedClaimsRevenueNotYetRecognized" abstract="false" name="UnsubmittedClaimsRevenueNotYetRecognized" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_AccruedClinicalAndCostOfOtherStudiesCurrent" abstract="false" name="AccruedClinicalAndCostOfOtherStudiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_TaxesPaidRelatedToNetShareSettlementOfRestrictedStockUnits" abstract="false" name="TaxesPaidRelatedToNetShareSettlementOfRestrictedStockUnits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_EmployeeAndNonEmployeeStockOptionsMember" abstract="true" name="EmployeeAndNonEmployeeStockOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_LeasesCommencedInAugust2022Member" abstract="true" name="LeasesCommencedInAugust2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNumberOfSharesOutstandingRollForward" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNumberOfSharesOutstandingRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardRepurchasesOfCommonStockUnderEmployeeIncentivePlans" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardRepurchasesOfCommonStockUnderEmployeeIncentivePlans" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cdna_DeferredPaymentsForIntangibleAssets" abstract="false" name="DeferredPaymentsForIntangibleAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingNumber" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardCommonStockAwardsForServices" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCommonStockAwardsForServices" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="cdna_CAREDXINCVsNateraIncMember" abstract="true" name="CAREDXINCVsNateraIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_MarketableSecuritiesAmortizedCost" abstract="false" name="MarketableSecuritiesAmortizedCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_ScheduleOfIntangibleAssetsTableTableTextBlock" abstract="false" name="ScheduleOfIntangibleAssetsTableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="cdna_AlloSureHeartMember" abstract="true" name="AlloSureHeartMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_EarningsPerShareBasicAndDilutedOtherDisclosureAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedOtherDisclosureAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_AtTheMarketEquityOfferingMember" abstract="true" name="AtTheMarketEquityOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_AccruedLicenseAndOtherCollaborationFees" abstract="false" name="AccruedLicenseAndOtherCollaborationFees" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_MarketableSecuritiesFairValueShortTerm" abstract="false" name="MarketableSecuritiesFairValueShortTerm" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="cdna_ScheduleOfFiniteAndInfiniteLivedIntangibleAssetsLineItems" abstract="true" name="ScheduleOfFiniteAndInfiniteLivedIntangibleAssetsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_SummaryOfSignificantAccountingPoliciesLineItems" abstract="true" name="SummaryOfSignificantAccountingPoliciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_SummaryOfSignificantAccountingPoliciesTable" abstract="true" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="cdna_MedicareMember" abstract="true" name="MedicareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_NumberOfMilestonePayments" abstract="false" name="NumberOfMilestonePayments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cdna_CostOfTestingMember" abstract="true" name="CostOfTestingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedOutstandingAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_EarningPerShareBasicAndDilutedAbstract" abstract="true" name="EarningPerShareBasicAndDilutedAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="cdna_NumberOfWarrantsExercised" abstract="false" name="NumberOfWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cdna_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNumberOfRSUSharesRollForward" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNumberOfRSUSharesRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cdna_NumberOfRenalTransplantPatients" abstract="false" name="NumberOfRenalTransplantPatients" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="cdna_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesContingentConsiderationsLessCurrentPortion" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesContingentConsiderationsLessCurrentPortion" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_CostOfProductMember" abstract="true" name="CostOfProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_AcquiredAndDevelopedTechnologyMember" abstract="true" name="AcquiredAndDevelopedTechnologyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_XynManagementIncMember" abstract="true" name="XynManagementIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_LeasesCommencedInJuly2022Member" abstract="true" name="LeasesCommencedInJuly2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cdna_ScheduleOfFiniteAndInfiniteLivedIntangibleAssetsTable" abstract="true" name="ScheduleOfFiniteAndInfiniteLivedIntangibleAssetsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="cdna_MarketableSecuritiesAmortizedCostShortTerm" abstract="false" name="MarketableSecuritiesAmortizedCostShortTerm" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_IncreaseDecreaseInOperatingLeaseLiabilities" abstract="false" name="IncreaseDecreaseInOperatingLeaseLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cdna_CommonStockWarrantLiability" abstract="false" name="CommonStockWarrantLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
