<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2025 Workiva-->
<!--r:4e26f936-c470-4d05-a574-2cbfcb2a5807,g:060c5370-6299-41cd-a157-0e2046c6d095-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.genedx.com/role/DocumentandEntityInformationDocument" xlink:type="simple" xlink:href="wgs-20250618.xsd#DocumentandEntityInformationDocument"/>
  <link:definitionLink xlink:role="http://www.genedx.com/role/DocumentandEntityInformationDocument" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_0dcc3431-49ef-4c81-8fb6-037f289ad6a5" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntitiesTable_0dcc3431-49ef-4c81-8fb6-037f289ad6a5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_45700131-f618-45d2-961a-75896de8cba5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_0dcc3431-49ef-4c81-8fb6-037f289ad6a5" xlink:to="loc_us-gaap_StatementClassOfStockAxis_45700131-f618-45d2-961a-75896de8cba5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_45700131-f618-45d2-961a-75896de8cba5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_45700131-f618-45d2-961a-75896de8cba5" xlink:to="loc_us-gaap_ClassOfStockDomain_45700131-f618-45d2-961a-75896de8cba5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_03923fef-d494-4012-b892-26f960bb73eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_45700131-f618-45d2-961a-75896de8cba5" xlink:to="loc_us-gaap_ClassOfStockDomain_03923fef-d494-4012-b892-26f960bb73eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_9105a228-04bc-403c-9e92-56cb941bfd27" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_03923fef-d494-4012-b892-26f960bb73eb" xlink:to="loc_us-gaap_CommonClassAMember_9105a228-04bc-403c-9e92-56cb941bfd27" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_68b64462-cd4a-46a5-802f-d7c0cee56bae" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_03923fef-d494-4012-b892-26f960bb73eb" xlink:to="loc_us-gaap_WarrantMember_68b64462-cd4a-46a5-802f-d7c0cee56bae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_f2d587ed-fab5-402c-87b0-5759a3451fcc" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_DocumentType_f2d587ed-fab5-402c-87b0-5759a3451fcc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_9e8923ec-47b1-4469-8ae9-b19dd1b00015" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_DocumentPeriodEndDate_9e8923ec-47b1-4469-8ae9-b19dd1b00015" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_93428da4-2d26-44f5-aeb3-208832e6e41a" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityRegistrantName_93428da4-2d26-44f5-aeb3-208832e6e41a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_bf730cb9-2496-4497-94c9-bc2a3258b3b4" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityIncorporationStateCountryCode_bf730cb9-2496-4497-94c9-bc2a3258b3b4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_b7cd12ce-4608-445f-b701-39f75347af67" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityFileNumber_b7cd12ce-4608-445f-b701-39f75347af67" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_70eb58cd-39f6-48c3-9515-08a15aa211df" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityTaxIdentificationNumber_70eb58cd-39f6-48c3-9515-08a15aa211df" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_1f409e7d-69c7-41d3-83b4-887bb533a44c" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressAddressLine1_1f409e7d-69c7-41d3-83b4-887bb533a44c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_cc8bc1fe-1651-41ce-b19a-168b2d2a7db3" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressCityOrTown_cc8bc1fe-1651-41ce-b19a-168b2d2a7db3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_1861d56b-6e6e-4989-9817-901d64723b69" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressStateOrProvince_1861d56b-6e6e-4989-9817-901d64723b69" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_8040caa5-9285-4801-a739-78d384fb19b0" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressPostalZipCode_8040caa5-9285-4801-a739-78d384fb19b0" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_bde04b16-807a-449c-b814-c69fdddccbad" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_CityAreaCode_bde04b16-807a-449c-b814-c69fdddccbad" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_e4f20250-7c38-4628-a6bd-b26ea0458ae0" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_LocalPhoneNumber_e4f20250-7c38-4628-a6bd-b26ea0458ae0" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_71b3407f-48a3-45fb-a787-a037c6b840d1" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_WrittenCommunications_71b3407f-48a3-45fb-a787-a037c6b840d1" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_9c6c6f17-8833-4a3e-9600-e36bc849033d" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_SolicitingMaterial_9c6c6f17-8833-4a3e-9600-e36bc849033d" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_19a4219f-172f-4c3a-994a-504ea1cd4273" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_PreCommencementTenderOffer_19a4219f-172f-4c3a-994a-504ea1cd4273" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_062c8386-7048-4f75-83a4-40d3bd267a9b" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_062c8386-7048-4f75-83a4-40d3bd267a9b" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_3bf8ce1f-43ed-412b-850c-a876f8861f04" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_Security12bTitle_3bf8ce1f-43ed-412b-850c-a876f8861f04" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_dc8c83f7-99f6-4bcb-a1c2-fac55ea132b6" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_TradingSymbol_dc8c83f7-99f6-4bcb-a1c2-fac55ea132b6" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_48595394-9bf5-4018-bacd-8597ac1308bf" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_SecurityExchangeName_48595394-9bf5-4018-bacd-8597ac1308bf" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_986cd687-7f7e-4333-a090-3452ca137d68" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityEmergingGrowthCompany_986cd687-7f7e-4333-a090-3452ca137d68" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityExTransitionPeriod_a8775e22-b07a-4b01-a336-a97a24c777da" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityExTransitionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityExTransitionPeriod_a8775e22-b07a-4b01-a336-a97a24c777da" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_452f7372-67f6-40d5-81df-670eddebf495" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressAddressLine2_452f7372-67f6-40d5-81df-670eddebf495" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine3_5d556139-cd5c-44b3-b7c8-c7c8e42a56a2" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityAddressAddressLine3_5d556139-cd5c-44b3-b7c8-c7c8e42a56a2" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_f0e9040d-23f0-48a1-b12e-5b9561d4d1b2" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_EntityCentralIndexKey_f0e9040d-23f0-48a1-b12e-5b9561d4d1b2" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_e1ba12b7-3b50-463f-9fae-196bf22d8ceb" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_3e67f16f-51c4-43ab-be66-267bceb4572a" xlink:to="loc_dei_AmendmentFlag_e1ba12b7-3b50-463f-9fae-196bf22d8ceb" xlink:type="arc" order="24"/>
  </link:definitionLink>
</link:linkbase>
