<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2021-03-15T03:33:31.8433617+00:00 -->
<!-- Version            : 5.0.1.571 -->
<!-- Package ID         : aa0a4891a9a44e0488d48d69a8fb6f0d -->
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="beam_InterestAndOtherIncomeExpenseNet" name="InterestAndOtherIncomeExpenseNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_AvailableForSaleSecuritiesTransferredSecurityUnrealizedGainLoss" name="AvailableForSaleSecuritiesTransferredSecurityUnrealizedGainLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_OtherOperatingIncomeExpenseAbstract" name="OtherOperatingIncomeExpenseAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ReconciliationOfNetGainLossToNetLossAttributableToCommonStockholdersAbstract" name="ReconciliationOfNetGainLossToNetLossAttributableToCommonStockholdersAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponClosingOfInitialPublicOfferingShares" name="TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponClosingOfInitialPublicOfferingShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponClosingOfInitialPublicOfferingValue" name="TemporaryEquityConversionOfRedeemableConvertiblePreferredStockToCommonStockUponClosingOfInitialPublicOfferingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_AccretionOfRedeemableConvertiblePreferredStockToRedemptionValue" name="AccretionOfRedeemableConvertiblePreferredStockToRedemptionValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_StockIssuedDuringPeriodValueVestingOfRestrictedCommonStock" name="StockIssuedDuringPeriodValueVestingOfRestrictedCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_IssuanceOfCommonStockValueRelatedToLicenseAgreement" name="IssuanceOfCommonStockValueRelatedToLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_OctoberTwoThousandTwentyPublicOfferingMember" name="OctoberTwoThousandTwentyPublicOfferingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_StockIssuedDuringPeriodSharesVestingOfRestrictedCommonStock" name="StockIssuedDuringPeriodSharesVestingOfRestrictedCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_IssuanceOfCommonStockSharesRelatedToLicenseAgreement" name="IssuanceOfCommonStockSharesRelatedToLicenseAgreement" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_TemporaryEquityNetIssuanceCost" name="TemporaryEquityNetIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_InitialPublicOfferingNetOfIssuanceCosts" name="InitialPublicOfferingNetOfIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_SeriesBRedeemableConvertiblePreferredStockMember" name="SeriesBRedeemableConvertiblePreferredStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ChangeInOperatingLeaseRightOfUseAssets" name="ChangeInOperatingLeaseRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_NonCashResearchAndDevelopmentLicenseExpense" name="NonCashResearchAndDevelopmentLicenseExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_ChangeInFairValueOfDerivativeLiabilities" name="ChangeInFairValueOfDerivativeLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_IncreaseDecreaseInOperatingLeaseLiabilities" name="IncreaseDecreaseInOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_IncreaseDecreaseInFinancingMilestoneLiabilities" name="IncreaseDecreaseInFinancingMilestoneLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_ProceedsFromEquipmentFinancings" name="ProceedsFromEquipmentFinancings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_RepaymentOfEquipmentFinancings" name="RepaymentOfEquipmentFinancings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_ReceiptOfCommonStockInExchangeForTechnologyLicense" name="ReceiptOfCommonStockInExchangeForTechnologyLicense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_EquityIssuanceCostsInAccountsPayableAndAccruedExpenses" name="EquityIssuanceCostsInAccountsPayableAndAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_LeasesDisclosureTextBlock" name="LeasesDisclosureTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_LicenseAgreementDisclosureTextBlock" name="LicenseAgreementDisclosureTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_EquityIssuanceCostsPoliciesPolicyTextBlock" name="EquityIssuanceCostsPoliciesPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_FreestandingFinancialInstrumentsAndDerivativesPolicyTextBlock" name="FreestandingFinancialInstrumentsAndDerivativesPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_PatentCostsPolicyPolicyTextBlock" name="PatentCostsPolicyPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ScheduleOfPropertyAndEquipmentEstimatedUsefulLifeTableTextBlock" name="ScheduleOfPropertyAndEquipmentEstimatedUsefulLifeTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_SummaryOfDepreciationExpenseIncurredTableTextBlock" name="SummaryOfDepreciationExpenseIncurredTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisSuccessPaymentDerivativeLiabilitiesTableTextBlock" name="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisSuccessPaymentDerivativeLiabilitiesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" name="ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_SummaryOfLeaseTermAndDiscountRateTableTextBlock" name="SummaryOfLeaseTermAndDiscountRateTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_SummaryOfLeaseCostsIncludedInMeasurementOfLeaseLiabilitiesTableTextBlock" name="SummaryOfLeaseCostsIncludedInMeasurementOfLeaseLiabilitiesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_SummaryOfPrincipalAndInterestPortionsTableTextBlock" name="SummaryOfPrincipalAndInterestPortionsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ScheduleOfSuccessPaymentLiabilityTableTextBlock" name="ScheduleOfSuccessPaymentLiabilityTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ScheduleOfChangeInFairValueOfSuccessPaymentLiabilityTableTextBlock" name="ScheduleOfChangeInFairValueOfSuccessPaymentLiabilityTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_NatureOfBusinessAndBasisOfPresentationLineItems" name="NatureOfBusinessAndBasisOfPresentationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_NatureOfBusinessAndBasisOfPresentationTable" name="NatureOfBusinessAndBasisOfPresentationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ComputerEquipmentAndSoftwareMember" name="ComputerEquipmentAndSoftwareMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_LaboratoryEquipmentAndOfficeFurnitureMember" name="LaboratoryEquipmentAndOfficeFurnitureMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_LabEquipmentMember" name="LabEquipmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_InterestAndOtherIncomeExpenseMember" name="InterestAndOtherIncomeExpenseMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_HarvardLicenseAgreementMember" name="HarvardLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_BroadLicenseAgreementMember" name="BroadLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_MeasurementInputFairValueOfPreferredStockMember" name="MeasurementInputFairValueOfPreferredStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_MeasurementInputFairValueOfCommonStockMember" name="MeasurementInputFairValueOfCommonStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_FairValueOfPreferredStockPricePerShareAfterAdjustedReverseStockSplit" name="FairValueOfPreferredStockPricePerShareAfterAdjustedReverseStockSplit" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="beam_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisSuccessPaymentLiabilityPeriodIncreaseDecrease" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisSuccessPaymentLiabilityPeriodIncreaseDecrease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisSuccessPaymentLiabilityValue" name="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisSuccessPaymentLiabilityValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_AccruedProcessDevelopmentAndManufacturingCosts" name="AccruedProcessDevelopmentAndManufacturingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_AccruedOtherResearchCosts" name="AccruedOtherResearchCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_OtherAccruedExpensesAndOtherCurrentLiabilities" name="OtherAccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_OperatingLeaseCommencementMonthAndYear" name="OperatingLeaseCommencementMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_OperatingLeaseTerminationMonthAndYear" name="OperatingLeaseTerminationMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_OfficeAndLaboratorySpaceMember" name="OfficeAndLaboratorySpaceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_LaboratorySpaceMember" name="LaboratorySpaceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_CommencementOfFirstPhaseOfLeaseInOctoberTwentyTwentyMember" name="CommencementOfFirstPhaseOfLeaseInOctoberTwentyTwentyMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_CommencementOfSecondPhaseOfLeaseExpectedToOccurFirstHalfOfTwentyTwentyOneMember" name="CommencementOfSecondPhaseOfLeaseExpectedToOccurFirstHalfOfTwentyTwentyOneMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_AlexandriaRealEstateEquitiesIncMember" name="AlexandriaRealEstateEquitiesIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_OperatingLeaseAmendmentMonthAndYear" name="OperatingLeaseAmendmentMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_LesseeOperatingLeaseLeaseNotYetCommencedExpirationTerm" name="LesseeOperatingLeaseLeaseNotYetCommencedExpirationTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_LesseeOperatingLeaseLeaseNotYetCommencedTenantImprovement" name="LesseeOperatingLeaseLeaseNotYetCommencedTenantImprovement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_LesseeOperatingLeaseLeaseNotYetCommencedSecurityDeposit" name="LesseeOperatingLeaseLeaseNotYetCommencedSecurityDeposit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_LesseeOperatingLeaseLeaseNotYetCommencedAnticipatedUndiscountedLeasePaymentsDue" name="LesseeOperatingLeaseLeaseNotYetCommencedAnticipatedUndiscountedLeasePaymentsDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_OperatingLeaseLiabilitiesArisingFromObtainingRightOfUseAssets" name="OperatingLeaseLiabilitiesArisingFromObtainingRightOfUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_ManufacturingFacilityNumberOfSquareFeet" name="ManufacturingFacilityNumberOfSquareFeet" type="num:areaItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_NumberOfOperatingLeaseRenewalOptions" name="NumberOfOperatingLeaseRenewalOptions" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ExpectsToInvestmentInLeaseAmount" name="ExpectsToInvestmentInLeaseAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_MaximumPeriodOfAmountExpectedToInvestInLease" name="MaximumPeriodOfAmountExpectedToInvestInLease" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ReimbursementOfTenantImprovements" name="ReimbursementOfTenantImprovements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_FinanceLeaseCertainEquipmentSoldAmount" name="FinanceLeaseCertainEquipmentSoldAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_FinancingObligationsLeaseBackEquipmentAnnualRentAmount" name="FinancingObligationsLeaseBackEquipmentAnnualRentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_FinanceLeaseAdditionalEquipmentSoldAmount" name="FinanceLeaseAdditionalEquipmentSoldAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_FinanceLeaseLiabilityPaymentsLineItems" name="FinanceLeaseLiabilityPaymentsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_FinanceLeaseLiabilityPaymentsTable" name="FinanceLeaseLiabilityPaymentsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_FinanceLeaseLiabilityPaymentsInterestPercentage" name="FinanceLeaseLiabilityPaymentsInterestPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="beam_SuccessPayments" name="SuccessPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_SuccessPaymentsValuationMultiples" name="SuccessPaymentsValuationMultiples" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_FirstSuccessPaymentMeasurementPeriod" name="FirstSuccessPaymentMeasurementPeriod" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ObligatedToPayForProductDevelopmentAndRegulatoryApprovalMilestonesPayment" name="ObligatedToPayForProductDevelopmentAndRegulatoryApprovalMilestonesPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_ProductMilestonePayments" name="ProductMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_EditasLicenseAgreementMember" name="EditasLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_BioPaletteLicenseAgreementMember" name="BioPaletteLicenseAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_BioPalettePatentMember" name="BioPalettePatentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_PaymentOfUpfrontFee" name="PaymentOfUpfrontFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_PaymentOfMilestoneAmount" name="PaymentOfMilestoneAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_CollaborationArrangementExtendTerm" name="CollaborationArrangementExtendTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_StockIssuedDuringPeriodSharesNewIssuesFromRelatedParty" name="StockIssuedDuringPeriodSharesNewIssuesFromRelatedParty" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_PrimeMedicineIncMember" name="PrimeMedicineIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_VerveMember" name="VerveMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_FixedUpfrontPaymentInFormNonCashConsideration" name="FixedUpfrontPaymentInFormNonCashConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_CommercialMilestonePaymentsOrRoyaltiesDue" name="CommercialMilestonePaymentsOrRoyaltiesDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="beam_TemporaryEquityIssuanceCosts" name="TemporaryEquityIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_RedeemableConvertiblePreferredStockLineItems" name="RedeemableConvertiblePreferredStockLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_RedeemableConvertiblePreferredStockTable" name="RedeemableConvertiblePreferredStockTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_TemporaryEquitySharesIssuedAndOutstanding" name="TemporaryEquitySharesIssuedAndOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="beam_SeriesAOneRedeemableConvertiblePreferredStockMember" name="SeriesAOneRedeemableConvertiblePreferredStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_SeriesATwoRedeemableConvertiblePreferredStockMember" name="SeriesATwoRedeemableConvertiblePreferredStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_BioPaletteCompanyLimitedMember" name="BioPaletteCompanyLimitedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_CommonStockNumberOfVotesPerShare" name="CommonStockNumberOfVotesPerShare" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_TwoThousandSeventeenStockOptionAndGrantPlanMember" name="TwoThousandSeventeenStockOptionAndGrantPlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_StockOptionsAndRestrictedStockMember" name="StockOptionsAndRestrictedStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_NonStatutoryOptionsMember" name="NonStatutoryOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_EmployeesOfficersFoundersAndConsultantsMember" name="EmployeesOfficersFoundersAndConsultantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_EmployeesOfficersBoardOfDirectorsAndConsultantsMember" name="EmployeesOfficersBoardOfDirectorsAndConsultantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_TwoThousandNineteenEquityIncentivePlanMember" name="TwoThousandNineteenEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_PerformanceBasedStockOptionsMember" name="PerformanceBasedStockOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ScientificFoundersMember" name="ScientificFoundersMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_TwoThousandNineteenEmployeeStockPurchasePlanMember" name="TwoThousandNineteenEmployeeStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_EmployeesMember" name="EmployeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfExercisePricePerShareOfStockOptionsOnFairMarketValueOfCommonStock" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfExercisePricePerShareOfStockOptionsOnFairMarketValueOfCommonStock" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageRemainingContractualLifeAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageRemainingContractualLifeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ShareBasedCompensationArrangementByShareBasedPaymentAwardAggregateIntrinsicValueAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAggregateIntrinsicValueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseInNumberOfSharesReservedAndAvailableForIssuance" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseInNumberOfSharesReservedAndAvailableForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="beam_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilitiesAndOther" name="DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilitiesAndOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_DeferredTaxAssetsAmortization" name="DeferredTaxAssetsAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_DeferredTaxAssetsLeasingArrangements" name="DeferredTaxAssetsLeasingArrangements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_TaxYear2018And2019And2020Member" name="TaxYear2018And2019And2020Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_FederalAndStateNetOperatingLossCarryforwardsExpirationStartPeriod" name="FederalAndStateNetOperatingLossCarryforwardsExpirationStartPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_TaxCreditsExpirationStartingYear" name="TaxCreditsExpirationStartingYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_OperatingLossCarryforwardNotSubjectToExpiration" name="OperatingLossCarryforwardNotSubjectToExpiration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_NumberOfFounderShareholders" name="NumberOfFounderShareholders" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_FounderShareholdersMember" name="FounderShareholdersMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ScientificConsultingAndOtherExpensesMember" name="ScientificConsultingAndOtherExpensesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_VerveTherapeuticsIncMember" name="VerveTherapeuticsIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_DefinedContributionPlanName" name="DefinedContributionPlanName" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="beam_GuideTherapeuticsIncorporatedMember" name="GuideTherapeuticsIncorporatedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_MergerAgreementMember" name="MergerAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_ProductSuccessMilestonePaymentsMember" name="ProductSuccessMilestonePaymentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="beam_PaymentOfAggregateAmountToStockholdersAndOptionHoldersUpfrontConsiderationExcludingCustomaryPurchaseAdjustments" name="PaymentOfAggregateAmountToStockholdersAndOptionHoldersUpfrontConsiderationExcludingCustomaryPurchaseAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="beam_MergerAgreementDescription" name="MergerAgreementDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
</xsd:schema>
