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  <xs:element id="gern_PublicOfferingStockIssuedDuringPeriodSharesNewIssues" abstract="false" name="PublicOfferingStockIssuedDuringPeriodSharesNewIssues" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_PublicOfferingStockIssuedDuringPeriodValueNewIssues" abstract="false" name="PublicOfferingStockIssuedDuringPeriodValueNewIssues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_IssuanceOfCommonStockInConnectionWithWarrantExerciseShares" abstract="false" name="IssuanceOfCommonStockInConnectionWithWarrantExerciseShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_IssuanceOfCommonStockInConnectionWithWarrantExerciseValue" abstract="false" name="IssuanceOfCommonStockInConnectionWithWarrantExerciseValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_StockIssuedDuringPeriodSharesExerciseOfPrefundedWarrant" abstract="false" name="StockIssuedDuringPeriodSharesExerciseOfPrefundedWarrant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_StockIssuedDuringPeriodValueExerciseOfPrefundedWarrant" abstract="false" name="StockIssuedDuringPeriodValueExerciseOfPrefundedWarrant" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_PublicOfferingOfCommonStockAndWarrantsMember" abstract="true" name="PublicOfferingOfCommonStockAndWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_NoncashInterestExpenseOnLiabilitiesForSalesOfFutureRoyalties" abstract="false" name="NoncashInterestExpenseOnLiabilitiesForSalesOfFutureRoyalties" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_IncreaseDecreaseInAllowanceForDoubtfulAccounts" abstract="false" name="IncreaseDecreaseInAllowanceForDoubtfulAccounts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_PaymentsUnpaidToAcquirePropertyPlantAndEquipment" abstract="false" name="PaymentsUnpaidToAcquirePropertyPlantAndEquipment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_ProceedsFromPublicOfferingIssuanceOfCommonStockAndWarrants" abstract="false" name="ProceedsFromPublicOfferingIssuanceOfCommonStockAndWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_SignificantAccountingPoliciesPolicyPolicyTextBlock" abstract="false" name="SignificantAccountingPoliciesPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gern_ScheduleOfGrossToNetSalesAdjustmentsTableTextBlock" abstract="false" name="ScheduleOfGrossToNetSalesAdjustmentsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gern_ScheduleOfActivityWithinLiabilityRelatedToSaleOfFutureRoyaltiesTableTextBlock" abstract="false" name="ScheduleOfActivityWithinLiabilityRelatedToSaleOfFutureRoyaltiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gern_ShareBasedPaymentArrangementOptionRestrictedStockUnitPerformanceSharesActivityTableTextBlock" abstract="false" name="ShareBasedPaymentArrangementOptionRestrictedStockUnitPerformanceSharesActivityTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gern_RevenuesBeforeAdjustmentsMember" abstract="true" name="RevenuesBeforeAdjustmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ChargebacksAndCustomerCreditsMember" abstract="true" name="ChargebacksAndCustomerCreditsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_GovernmentRebatesMember" abstract="true" name="GovernmentRebatesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_SalesReturnsAndAllowanceMember" abstract="true" name="SalesReturnsAndAllowanceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TotalGrossToNetAdjustmentsMember" abstract="true" name="TotalGrossToNetAdjustmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_USTreasurySecuritiesDueInLessThanOneYearMember" abstract="true" name="USTreasurySecuritiesDueInLessThanOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_USTreasurySecuritiesDueInOneToTwoYearsMember" abstract="true" name="USTreasurySecuritiesDueInOneToTwoYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember" abstract="true" name="USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CommercialPaperDueInLessThanOneYearMember" abstract="true" name="CommercialPaperDueInLessThanOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CorporateNoteSecuritiesDueInLessThanOneYearMember" abstract="true" name="CorporateNoteSecuritiesDueInLessThanOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CorporateNoteSecuritiesDueInOneToTwoYearsMember" abstract="true" name="CorporateNoteSecuritiesDueInOneToTwoYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CashAndCashEquivalentsUnrealizedGains" abstract="false" name="CashAndCashEquivalentsUnrealizedGains" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_CashAndCashEquivalentsUnrealizedLosses" abstract="false" name="CashAndCashEquivalentsUnrealizedLosses" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_RestrictedCashAndCashEquivalentsGrossUnrealizedGains" abstract="false" name="RestrictedCashAndCashEquivalentsGrossUnrealizedGains" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_RestrictedCashAndCashEquivalentsGrossUnrealizedLosses" abstract="false" name="RestrictedCashAndCashEquivalentsGrossUnrealizedLosses" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_GovernmentSponsoredEnterpriseSecuritiesDueInLessThanOneYearMember" abstract="true" name="GovernmentSponsoredEnterpriseSecuritiesDueInLessThanOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CashAndCashEquivalentsAndRestrictedCashFairValueDisclosure" abstract="false" name="CashAndCashEquivalentsAndRestrictedCashFairValueDisclosure" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_FourCustomersMember" abstract="true" name="FourCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_McKessonFinancialCenterMember" abstract="true" name="McKessonFinancialCenterMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ASDSpecialtyHealthcareLLCMember" abstract="true" name="ASDSpecialtyHealthcareLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CardinalHealthIncMember" abstract="true" name="CardinalHealthIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_SinaDrugMember" abstract="true" name="SinaDrugMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_AccruedClinicalResearchOrganizationsAndClinicalTrialCostsCurrent" abstract="false" name="AccruedClinicalResearchOrganizationsAndClinicalTrialCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_AccruedManufacturingActivitiesCurrent" abstract="false" name="AccruedManufacturingActivitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_AccruedRevenueAdjustments" abstract="false" name="AccruedRevenueAdjustments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_BiopharmaCreditPlcMember" abstract="true" name="BiopharmaCreditPlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PharmakonLoanAgreementMember" abstract="true" name="PharmakonLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_RoyaltyPharmaRevenueParticipationRightPurchaseAgreementMember" abstract="true" name="RoyaltyPharmaRevenueParticipationRightPurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TrancheAMember" abstract="true" name="TrancheAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TrancheBMember" abstract="true" name="TrancheBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TrancheCMember" abstract="true" name="TrancheCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TermLoansMember" abstract="true" name="TermLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PrepaidPriorToThirdAnniversaryOfFundingDateMember" abstract="true" name="PrepaidPriorToThirdAnniversaryOfFundingDateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PrepaidOnOrAfterThirdAnniversaryButPriorToFourthAnniversaryOfFundingDateMember" abstract="true" name="PrepaidOnOrAfterThirdAnniversaryButPriorToFourthAnniversaryOfFundingDateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PrepaidOnOrAfterFourthAnniversaryOfFundingDateMember" abstract="true" name="PrepaidOnOrAfterFourthAnniversaryOfFundingDateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_DebtInstrumentScenarioAxis" abstract="true" name="DebtInstrumentScenarioAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="gern_DebtInstrumentScenarioDomain" abstract="true" name="DebtInstrumentScenarioDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ScenarioOneMember" abstract="true" name="ScenarioOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ScenarioTwoMember" abstract="true" name="ScenarioTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_DebtInstrumentFloorRate" abstract="false" name="DebtInstrumentFloorRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gern_PercentageOfCommitmentAmountToFundLoan" abstract="false" name="PercentageOfCommitmentAmountToFundLoan" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gern_PrepaymentPremiumOnPercentageOfTermLoan" abstract="false" name="PrepaymentPremiumOnPercentageOfTermLoan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gern_UpfrontPaymentReceived" abstract="false" name="UpfrontPaymentReceived" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_PercentageOfAnnualNetSales" abstract="false" name="PercentageOfAnnualNetSales" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gern_DebtInstrumentRoyaltyPaymentRatio" abstract="false" name="DebtInstrumentRoyaltyPaymentRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="gern_LongTermDebtMaturityAfterYearFour" abstract="false" name="LongTermDebtMaturityAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gern_RoyaltiesRollForward" abstract="true" name="RoyaltiesRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="gern_SeverancePlanTable" abstract="true" name="SeverancePlanTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="gern_SeverancePlanLineItems" abstract="true" name="SeverancePlanLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="gern_PurchaseObligationWrittenNoticeTerm" abstract="false" name="PurchaseObligationWrittenNoticeTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gern_PublicOfferingTable" abstract="true" name="PublicOfferingTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="gern_TwoThousandTwentyFourUnderwrittenPublicOfferingMember" abstract="true" name="TwoThousandTwentyFourUnderwrittenPublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TwoThousandTwentyFourPreFundedWarrantMember" abstract="true" name="TwoThousandTwentyFourPreFundedWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PublicOfferingLineItems" abstract="true" name="PublicOfferingLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="gern_ShareOfCommonStockIssuedDuringPeriodSharesNewIssuesPublicOffering" abstract="false" name="ShareOfCommonStockIssuedDuringPeriodSharesNewIssuesPublicOffering" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_TwoThousandTwentyFiveUnderwrittenPublicOfferingMember" abstract="true" name="TwoThousandTwentyFiveUnderwrittenPublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TwoThousandTwentyPublicOfferingOfCommonStockAndWarrantsMember" abstract="true" name="TwoThousandTwentyPublicOfferingOfCommonStockAndWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_TwoThousandTwentyFivePreFundedWarrantMember" abstract="true" name="TwoThousandTwentyFivePreFundedWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_PreFundedWarrantsMember" abstract="true" name="PreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_StockPurchaseWarrantsMember" abstract="true" name="StockPurchaseWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedOutstandingNumber" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedOutstandingNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gern_ResearchAndClinicalExpensesMember" abstract="true" name="ResearchAndClinicalExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ChemistryManufacturingAndControlExpensesMember" abstract="true" name="ChemistryManufacturingAndControlExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_CommercialExpensesMember" abstract="true" name="CommercialExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_SusanMolineauxMember" abstract="true" name="SusanMolineauxMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gern_JohnA.ScarlettMember" abstract="true" name="JohnA.ScarlettMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
