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  <xsd:element id="fdmt_AdditionalFundingCommitted" name="AdditionalFundingCommitted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AdditionalInvestmentInCash" name="AdditionalInvestmentInCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AdjustmentsToAdditionalPaidInCapitalVestingOfStockWarrantIssuedForServices" name="AdjustmentsToAdditionalPaidInCapitalVestingOfStockWarrantIssuedForServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AmountObligatedToPayNonRefundableLicenseFeeAnnually" name="AmountObligatedToPayNonRefundableLicenseFeeAnnually" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AmountObligatedToPayUponClosingFirstQualifiedFinancingAtOption" name="AmountObligatedToPayUponClosingFirstQualifiedFinancingAtOption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AmountsPaidNonRefundableLicenseFees" name="AmountsPaidNonRefundableLicenseFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_AnnualRoyalty" name="AnnualRoyalty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CARESActReliefDescription" name="CARESActReliefDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CollaborationArrangementsContingentPaymentForEachNominatedProductBeyondFirstThree" name="CollaborationArrangementsContingentPaymentForEachNominatedProductBeyondFirstThree" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsDevelopmentMilestonePaymentsRelatingToChoroideremia" name="CollaborationArrangementsDevelopmentMilestonePaymentsRelatingToChoroideremia" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsMaximumContingentPaymentUponExerciseOfOptionToConvertAProduct" name="CollaborationArrangementsMaximumContingentPaymentUponExerciseOfOptionToConvertAProduct" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsMaximumDevelopmentMilestonePayments" name="CollaborationArrangementsMaximumDevelopmentMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsNonRefundableDevelopmentMilestonePayments" name="CollaborationArrangementsNonRefundableDevelopmentMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsNonRefundableUpfrontPaymentReceived" name="CollaborationArrangementsNonRefundableUpfrontPaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborationArrangementsUpfrontPaymentReceived" name="CollaborationArrangementsUpfrontPaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementAchievedMilestones" name="CollaborativeArrangementAchievedMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementAdditionalResearchTerm" name="CollaborativeArrangementAdditionalResearchTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CollaborativeArrangementAdditionOfVariableConsideration" name="CollaborativeArrangementAdditionOfVariableConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementAdjustmentToTransactionPrice" name="CollaborativeArrangementAdjustmentToTransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementContributionUponDevelopmentMilestone" name="CollaborativeArrangementContributionUponDevelopmentMilestone" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementIncreaseOfProjectScopeAndExpectedReimbursableCosts" name="CollaborativeArrangementIncreaseOfProjectScopeAndExpectedReimbursableCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_CollaborativeArrangementInitialResearchTerm" name="CollaborativeArrangementInitialResearchTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CollaborativeArrangementMaximumSalesBasedMilestonePayments" name="CollaborativeArrangementMaximumSalesBasedMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborativeArrangementResearchAndDevelopmentMilestonesEntitledToReceiveForEachLicensedProduct" name="CollaborativeArrangementResearchAndDevelopmentMilestonesEntitledToReceiveForEachLicensedProduct" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_CollaborativeArrangementsFutureSalesBasedMilestonePaymentsPercentage" name="CollaborativeArrangementsFutureSalesBasedMilestonePaymentsPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CollaborativeArrangementsRoyaltiesPercentageOnActualAwardReceived" name="CollaborativeArrangementsRoyaltiesPercentageOnActualAwardReceived" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CollaborativeArrangementTransactionPriceAdjustment" name="CollaborativeArrangementTransactionPriceAdjustment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_ContingentPaymentsEliminated" name="ContingentPaymentsEliminated" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_ContinuousPeriodWhereCompanyCeasesToDevelopOrCommercializeAnyProduct" name="ContinuousPeriodWhereCompanyCeasesToDevelopOrCommercializeAnyProduct" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_DeferredTaxAssetsOperatingLeaseLiabilities" name="DeferredTaxAssetsOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" name="DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_DevelopmentMilestones" name="DevelopmentMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_ExpectedPaymentsPercentageToEqualActualAwardReceived" name="ExpectedPaymentsPercentageToEqualActualAwardReceived" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_FairValueAssumptionsChangeOfControlPayment" name="FairValueAssumptionsChangeOfControlPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_FairValueAssumptionsProbabilityOfChangeInControlDiscountRate" name="FairValueAssumptionsProbabilityOfChangeInControlDiscountRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_FairValueAssumptionsProbabilityOfChangeInControlEventPercentage" name="FairValueAssumptionsProbabilityOfChangeInControlEventPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_FairValueOfNonMonetaryConsiderationOfIntellectualPropertyRight" name="FairValueOfNonMonetaryConsiderationOfIntellectualPropertyRight" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_FairValueOfOptions" name="FairValueOfOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_IncreaseDecreaseInContractWithCustomerRevenueRecognized" name="IncreaseDecreaseInContractWithCustomerRevenueRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_IncurredExpenses" name="IncurredExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_IssuanceCostForIssuanceOfPreferredStock" name="IssuanceCostForIssuanceOfPreferredStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_IssuanceOfCommonStockUponExerciseOfStockOptionsAndWarrants" name="IssuanceOfCommonStockUponExerciseOfStockOptionsAndWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_LeaseIncentiveLiability" name="LeaseIncentiveLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_MaximumMaturityPeriodOfMarketableSecurities" name="MaximumMaturityPeriodOfMarketableSecurities" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_MinimumPercentageOfOutstandingSharesHeldByIndividual" name="MinimumPercentageOfOutstandingSharesHeldByIndividual" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_NonCashIssuanceOfCommonStockWarrantToSettleLiability" name="NonCashIssuanceOfCommonStockWarrantToSettleLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_NonRefundableLicenseFeePayableEveryYearAfterExecution" name="NonRefundableLicenseFeePayableEveryYearAfterExecution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_NonRefundableLicenseFeePayableUponExecution" name="NonRefundableLicenseFeePayableUponExecution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_NumberOfAgreementsEntered" name="NumberOfAgreementsEntered" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_NumberOfFinancialInstitutionsWhereCashIsHeld" name="NumberOfFinancialInstitutionsWhereCashIsHeld" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_NumberOfInstallmentsToPayActualAward" name="NumberOfInstallmentsToPayActualAward" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_NumberOfMarketableSecuritiesUnrealizedLossPositionMoreThanOneYear" name="NumberOfMarketableSecuritiesUnrealizedLossPositionMoreThanOneYear" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_NumberOfWarrantsIssued" name="NumberOfWarrantsIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_OperatingLeaseTermExtendedExpirationPeriod" name="OperatingLeaseTermExtendedExpirationPeriod" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_OperatingLossCarryforwardsExpirationYear" name="OperatingLossCarryforwardsExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_OptionsToPurchaseOrdinaryShares" name="OptionsToPurchaseOrdinaryShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_PercentageOfEquityInterestsIssuedAsCommonStock" name="PercentageOfEquityInterestsIssuedAsCommonStock" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_PercentageOfEquityInterestUponClosingOfFirstQualifiedFinancingAtOption" name="PercentageOfEquityInterestUponClosingOfFirstQualifiedFinancingAtOption" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_PrepaidExpensesToRelatedPartiesCurrent" name="PrepaidExpensesToRelatedPartiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_ResearchAndDevelopmentExpenseRelatedParty" name="ResearchAndDevelopmentExpenseRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_ScheduleOfCommonShareReservedForFutureIssuance" name="ScheduleOfCommonShareReservedForFutureIssuance" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardDurationPurchasePeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardDurationPurchasePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePriceAsPercentageOfFairMarketValueMinimum" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePriceAsPercentageOfFairMarketValueMinimum" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockIncreasedAnnuallyForFutureIssuance" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockIncreasedAnnuallyForFutureIssuance" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantExpirationsInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantExpirationsInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantForfeituresInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantForfeituresInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantGrantsInPeriodGross" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAvailableForGrantGrantsInPeriodGross" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOverlappingOfferingPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockOverlappingOfferingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_StockIssuedDuringPeriodSharesStockOptionsAndWarrantsExercised" name="StockIssuedDuringPeriodSharesStockOptionsAndWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_StockIssuedDuringPeriodValueNetUnrealizedGainLossOnSaleOfMarketableSecurities" name="StockIssuedDuringPeriodValueNetUnrealizedGainLossOnSaleOfMarketableSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_StockIssuedDuringPeriodValueStockOptionsAndWarrantsExercised" name="StockIssuedDuringPeriodValueStockOptionsAndWarrantsExercised" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_TaxCreditCarryforwardBeginningExpirationYear" name="TaxCreditCarryforwardBeginningExpirationYear" type="dtr-types:gYearListItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_TaxCreditCarryforwardExpirationDescription" name="TaxCreditCarryforwardExpirationDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_TermOfAgreement" name="TermOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_UnpaidOfferingCosts" name="UnpaidOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdmt_VestingOfCommonStockWarrantInReturnForServices" name="VestingOfCommonStockWarrantInReturnForServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdmt_VestingPeriodOfShareAwards" name="VestingPeriodOfShareAwards" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_WarrantExercisedMonthAndYear" name="WarrantExercisedMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_WarrantExpiresYear" name="WarrantExpiresYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_WarrantVestsOverPeriod" name="WarrantVestsOverPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CommitmentAndContingenciesLineItems" name="CommitmentAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_OrganizationAndNatureOfBusinessLineItems" name="OrganizationAndNatureOfBusinessLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_AmendedUniQureAgreementMember" name="AmendedUniQureAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_BuildingLeaseAndExpansionMember" name="BuildingLeaseAndExpansionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_BuildingLeaseMember" name="BuildingLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_ChoroideremiaResearchFoundationAgreementMember" name="ChoroideremiaResearchFoundationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_ChoroideremiaResearchFoundationMember" name="ChoroideremiaResearchFoundationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CoFounderAndChiefScientificAdvisorMember" name="CoFounderAndChiefScientificAdvisorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CollaborationAndLicenseRevenueMember" name="CollaborationAndLicenseRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_ConsultingServicesAndServicesAsBoardOfDirectorMember" name="ConsultingServicesAndServicesAsBoardOfDirectorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CorporateBondMember" name="CorporateBondMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CustomerAMember" name="CustomerAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CustomerBMember" name="CustomerBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CustomerMember" name="CustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_CysticFibrosisFoundationMember" name="CysticFibrosisFoundationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_EmployeeMember" name="EmployeeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_FHoffmannLaRocheLtdAndHoffmannLaRocheIncMember" name="FHoffmannLaRocheLtdAndHoffmannLaRocheIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_FollowOnPublicOfferingMember" name="FollowOnPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_FundingAgreementProductMember" name="FundingAgreementProductMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_LongTermMarketableSecuritiesMember" name="LongTermMarketableSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_MachineLearningSponsoredResearchAgreementMember" name="MachineLearningSponsoredResearchAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_NonemployeeMember" name="NonemployeeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SeriesA1RedeemableConvertiblePreferredStockMember" name="SeriesA1RedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SeriesARedeemableConvertiblePreferredStockMember" name="SeriesARedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SeriesBFinancingMember" name="SeriesBFinancingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SeriesBRedeemableConvertiblePreferredStockMember" name="SeriesBRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SeriesCRedeemableConvertiblePreferredStockMember" name="SeriesCRedeemableConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_ShortTermMarketableSecuritiesMember" name="ShortTermMarketableSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SponsoredResearchAgreementsAndMachineLearningSponsoredResearchAgreementsMember" name="SponsoredResearchAgreementsAndMachineLearningSponsoredResearchAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SponsoredResearchAgreementsMember" name="SponsoredResearchAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandAndSeventeenRocheAgreementMember" name="TwoThousandAndSeventeenRocheAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandFifteenEquityIncentivePlanMember" name="TwoThousandFifteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandFourteenPlanMember" name="TwoThousandFourteenPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandTwentyEmployeeStockPurchasePlanMember" name="TwoThousandTwentyEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandTwentyEquityIncentivePlanMember" name="TwoThousandTwentyEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_TwoThousandTwentyIncentiveAwardPlanMember" name="TwoThousandTwentyIncentiveAwardPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_UCAgreementsMember" name="UCAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_UCRegentsMember" name="UCRegentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_UniQureAgreementMember" name="UniQureAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_UniQureBiopharmaBVMember" name="UniQureBiopharmaBVMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_AccruedResearchAndDevelopmentPolicyPolicyTextBlock" name="AccruedResearchAndDevelopmentPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CommonStockWarrantsPolicyPolicyTextBlock" name="CommonStockWarrantsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_DeferredOfferingCostsPolicyPolicyTextBlock" name="DeferredOfferingCostsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_OtherRisksAndUncertaintiesPolicyPolicyTextBlock" name="OtherRisksAndUncertaintiesPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_RedeemableConvertiblePreferredStockPolicyPolicyTextBlock" name="RedeemableConvertiblePreferredStockPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CommitmentAndContingenciesTable" name="CommitmentAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_OrganizationAndNatureOfBusinessTable" name="OrganizationAndNatureOfBusinessTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdmt_ScheduleOfCollaborationAndLicenseRevenueTableTextBlock" name="ScheduleOfCollaborationAndLicenseRevenueTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_AccruedAndOtherLiabilitiesTextBlock" name="AccruedAndOtherLiabilitiesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_CommonStockWarrantsTextBlock" name="CommonStockWarrantsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_LicenseArrangementsTextBlock" name="LicenseArrangementsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdmt_TemporaryEquityDisclosureTextBlock" name="TemporaryEquityDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
