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  <xsd:element id="rlay_MilestonePaymentReceived" name="MilestonePaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_MilestonePayments" name="MilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_NonRefundableMilestoneForCompletionAmount" name="NonRefundableMilestoneForCompletionAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_NonRefundableMilestoneTransferAmount" name="NonRefundableMilestoneTransferAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_NonRefundableUpfrontPayment" name="NonRefundableUpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_NumberOfDiscoveryStagePrograms" name="NumberOfDiscoveryStagePrograms" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rlay_NumberOfMilestoneTargets" name="NumberOfMilestoneTargets" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="rlay_NumberOfSharesWouldBeIssuedUponMilestoneAchievement" name="NumberOfSharesWouldBeIssuedUponMilestoneAchievement" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_PaymentRelatedToCollaborationOrOtherAgreements" name="PaymentRelatedToCollaborationOrOtherAgreements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_PercentageOfAdditionalCommonStockAuthorized" name="PercentageOfAdditionalCommonStockAuthorized" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_PercentageOfPaymentRelatedToCollaborationOrOtherAgreements" name="PercentageOfPaymentRelatedToCollaborationOrOtherAgreements" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_PotentialDevelopmentMilestonePayments" name="PotentialDevelopmentMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_ProceedsFromIssuanceOfCommonStockUponFollowOnOfferingNet" name="ProceedsFromIssuanceOfCommonStockUponFollowOnOfferingNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_ReclassificationOfRestrictedStockLiabilityToAdditionalPaidInCapital" name="ReclassificationOfRestrictedStockLiabilityToAdditionalPaidInCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_RegulatoryBasedMilestonePaymentsUnderAgreement" name="RegulatoryBasedMilestonePaymentsUnderAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_ResearchAndDevelopmentArrangementAnnualFee" name="ResearchAndDevelopmentArrangementAnnualFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_ResearchAndDevelopmentArrangementContractToPerformForOthersRenewalPeriod" name="ResearchAndDevelopmentArrangementContractToPerformForOthersRenewalPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ResearchAndDevelopmentArrangementExpirationDate" name="ResearchAndDevelopmentArrangementExpirationDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ResearchAndDevelopmentArrangementTermOfContract" name="ResearchAndDevelopmentArrangementTermOfContract" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_RestrictedStockLiability" name="RestrictedStockLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedWeightedAverageRemainingContractualTerm" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedWeightedAverageRemainingContractualTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ShareBasedCompensationByShareBasedArrangementEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAveragePriceOfSharesPurchased" name="ShareBasedCompensationByShareBasedArrangementEquityInstrumentsOtherThanOptionsCancelledInPeriodWeightedAveragePriceOfSharesPurchased" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ShareBasedCompensationByShareBasedArrangementEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAveragePriceOfSharesPurchased" name="ShareBasedCompensationByShareBasedArrangementEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAveragePriceOfSharesPurchased" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_StockIssuedDuringPeriodAdditionalSharesIssued" name="StockIssuedDuringPeriodAdditionalSharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_StockIssuedDuringPeriodSharesPreferredStockNetOfIssuanceCosts" name="StockIssuedDuringPeriodSharesPreferredStockNetOfIssuanceCosts" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_StockIssuedDuringPeriodValuePreferredStockNetOfIssuanceCosts" name="StockIssuedDuringPeriodValuePreferredStockNetOfIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_TaxCutsAndJobsActOf2017DescriptionOfCorporateTaxPayers" name="TaxCutsAndJobsActOf2017DescriptionOfCorporateTaxPayers" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_TaxCutsAndJobsActOf2017MaximumPercentageOfInterestDeductedByTaxPayers" name="TaxCutsAndJobsActOf2017MaximumPercentageOfInterestDeductedByTaxPayers" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_TaxCutsAndJobsActOf2017NetOperatingLossCarrybackPeriod" name="TaxCutsAndJobsActOf2017NetOperatingLossCarrybackPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_UpfrontConsiderationPayable" name="UpfrontConsiderationPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_VariableConsiderationRelatedToReimbursementsDueForResearchAndDevelopmentServices" name="VariableConsiderationRelatedToReimbursementsDueForResearchAndDevelopmentServices" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="rlay_VestingOfRestrictedCommonStockShares" name="VestingOfRestrictedCommonStockShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_VestingOfRestrictedCommonStockValue" name="VestingOfRestrictedCommonStockValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="rlay_CollaborationAndLicenseArrangementLineItems" name="CollaborationAndLicenseArrangementLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_CommitmentsAndContingenciesDisclosureLineItems" name="CommitmentsAndContingenciesDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_IncomeTaxDisclosureLineItems" name="IncomeTaxDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_NatureOfBusinessAndBasisOfPresentationLineItems" name="NatureOfBusinessAndBasisOfPresentationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_BinneyStreetCambridgeMassachusettsMember" name="BinneyStreetCambridgeMassachusettsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_BmrHampshireLlcMember" name="BmrHampshireLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_ConsultingAndManagementServicesMember" name="ConsultingAndManagementServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_ConvertiblePreferredStocksMember" name="ConvertiblePreferredStocksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_CowenMember" name="CowenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_DEShawResearchMember" name="DEShawResearchMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_EarnoutPaymentsMember" name="EarnoutPaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_EqrxIncMember" name="EqrxIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_GenentechAgreementMember" name="GenentechAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_GenentechIncMember" name="GenentechIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_InvestmentsWithMaturityOfOneToTwoYearsMember" name="InvestmentsWithMaturityOfOneToTwoYearsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_InvestmentsWithMaturityOfOneYearOrLessMember" name="InvestmentsWithMaturityOfOneYearOrLessMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_LaboratoryAndComputerEquipmentMember" name="LaboratoryAndComputerEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_LeaseAgreementMember" name="LeaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_LicenseAndTransferAgreementMember" name="LicenseAndTransferAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_MilestonePaymentsMember" name="MilestonePaymentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_OperatingLeaseAssetsMember" name="OperatingLeaseAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_OperatingLeaseLiabilitiesMember" name="OperatingLeaseLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_OperatingLeaseLiabilitiesNetOfCurrentPortionMember" name="OperatingLeaseLiabilitiesNetOfCurrentPortionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_OtherthirdPartiesMember" name="OtherthirdPartiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_PerformanceBasedStockOptionsMember" name="PerformanceBasedStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_ResearchAndDevelopmentServicesMember" name="ResearchAndDevelopmentServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_RestrictedSharesMember" name="RestrictedSharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_SalesAgreementMember" name="SalesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_StandAloneSellingPricesMember" name="StandAloneSellingPricesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_ThirdRockVentureMember" name="ThirdRockVentureMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_TimeBasedStockOptionsMember" name="TimeBasedStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_TransferOfActivePharmaceuticalIngredientsMember" name="TransferOfActivePharmaceuticalIngredientsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_TwoThousandSixteenPlanMember" name="TwoThousandSixteenPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_TwoThousandTwentyPlanMember" name="TwoThousandTwentyPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_UndesignatedpreferredstockMember" name="UndesignatedpreferredstockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_ZebiAITherapeuticsIncMember" name="ZebiAITherapeuticsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_CollaborationAndLicenseArrangementTable" name="CollaborationAndLicenseArrangementTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_CommitmentsAndContingenciesDisclosureTable" name="CommitmentsAndContingenciesDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_IncomeTaxDisclosureTable" name="IncomeTaxDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_NatureOfBusinessAndBasisOfPresentationTable" name="NatureOfBusinessAndBasisOfPresentationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="rlay_BasisOfPresentationPolicyTextBlock" name="BasisOfPresentationPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ConcentrationOfCreditRiskAndSignificantSuppliersPolicyTextBlock" name="ConcentrationOfCreditRiskAndSignificantSuppliersPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_DescriptionOfNewAccountingPronouncementsNotYetAdoptedPolicyTextBlock" name="DescriptionOfNewAccountingPronouncementsNotYetAdoptedPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_PatentCostsPolicyTextBlock" name="PatentCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ResearchAndManufacturingContractsPolicyTextBlock" name="ResearchAndManufacturingContractsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ReservedSharesOfCommonStockForFutureIssuanceTableTableTextBlock" name="ReservedSharesOfCommonStockForFutureIssuanceTableTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ScheduleOfChangesInFairValueOfContingentConsiderationLiabilityTableTextBlock" name="ScheduleOfChangesInFairValueOfContingentConsiderationLiabilityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_ScheduleOfOperatingLeasePresentationInConsolidatedBalanceSheetTableTextBlock" name="ScheduleOfOperatingLeasePresentationInConsolidatedBalanceSheetTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="rlay_SummaryOfOperatingLeasePresentationInConsolidatedStatementsOfOperationsAndComprehensiveLossTableTextBlock" name="SummaryOfOperatingLeasePresentationInConsolidatedStatementsOfOperationsAndComprehensiveLossTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
