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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019ba3f3-56db-7dc6-9fed-77f06db50276,g:94cd0ec3-5099-4bbf-a4b6-dc51bc875312-->
<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-20260112.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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_019ba3f3-56db-7e7a-b1ad-8e095cd6deb0" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntitiesTable_019ba3f3-56db-7e7a-b1ad-8e095cd6deb0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019ba3f3-56db-7a73-975f-35705315e224" 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_019ba3f3-56db-7e7a-b1ad-8e095cd6deb0" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019ba3f3-56db-7a73-975f-35705315e224" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019ba3f3-56db-7a73-975f-35705315e224_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_019ba3f3-56db-7a73-975f-35705315e224" xlink:to="loc_us-gaap_ClassOfStockDomain_019ba3f3-56db-7a73-975f-35705315e224_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019ba3f3-56db-7eb2-81ab-b8f529e91156" 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_019ba3f3-56db-7a73-975f-35705315e224" xlink:to="loc_us-gaap_ClassOfStockDomain_019ba3f3-56db-7eb2-81ab-b8f529e91156" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019ba3f3-56db-7d73-9c68-9e8505768503" 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_019ba3f3-56db-7eb2-81ab-b8f529e91156" xlink:to="loc_us-gaap_CommonClassAMember_019ba3f3-56db-7d73-9c68-9e8505768503" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_019ba3f3-56db-74d5-89bb-b10b8b7c0522" 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_019ba3f3-56db-7eb2-81ab-b8f529e91156" xlink:to="loc_us-gaap_WarrantMember_019ba3f3-56db-74d5-89bb-b10b8b7c0522" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019ba3f3-56db-7282-9932-9cc093e74a49" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_DocumentType_019ba3f3-56db-7282-9932-9cc093e74a49" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019ba3f3-56dc-77ff-95eb-16bb118fec9b" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_DocumentPeriodEndDate_019ba3f3-56dc-77ff-95eb-16bb118fec9b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019ba3f3-56dc-7d15-8eab-5750b57b6b9b" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityRegistrantName_019ba3f3-56dc-7d15-8eab-5750b57b6b9b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019ba3f3-56dc-7c15-897b-15b58d6e9ca4" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019ba3f3-56dc-7c15-897b-15b58d6e9ca4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019ba3f3-56dc-7157-8ae9-868284007355" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityFileNumber_019ba3f3-56dc-7157-8ae9-868284007355" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019ba3f3-56dc-7488-a04b-c94782dfd481" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityTaxIdentificationNumber_019ba3f3-56dc-7488-a04b-c94782dfd481" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019ba3f3-56dc-7385-aaa6-fb9c28ee78e2" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressAddressLine1_019ba3f3-56dc-7385-aaa6-fb9c28ee78e2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019ba3f3-56dc-7a2d-9b57-c93e1285733b" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressCityOrTown_019ba3f3-56dc-7a2d-9b57-c93e1285733b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019ba3f3-56dc-795a-af29-cbd8af309ec8" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressStateOrProvince_019ba3f3-56dc-795a-af29-cbd8af309ec8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019ba3f3-56dc-7eab-81b3-b4d91de95e78" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressPostalZipCode_019ba3f3-56dc-7eab-81b3-b4d91de95e78" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019ba3f3-56dc-728e-bf5a-445f966b2e89" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_CityAreaCode_019ba3f3-56dc-728e-bf5a-445f966b2e89" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019ba3f3-56dc-7126-bf50-d3b72f198271" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_LocalPhoneNumber_019ba3f3-56dc-7126-bf50-d3b72f198271" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019ba3f3-56dc-7734-ac15-18f831aafdf8" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_WrittenCommunications_019ba3f3-56dc-7734-ac15-18f831aafdf8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019ba3f3-56dc-7f86-88b7-95cf8c0fde6c" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_SolicitingMaterial_019ba3f3-56dc-7f86-88b7-95cf8c0fde6c" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019ba3f3-56dc-7733-b6a1-174672dcfa21" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_PreCommencementTenderOffer_019ba3f3-56dc-7733-b6a1-174672dcfa21" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019ba3f3-56dc-7a89-b3c1-7e111ba1ce1b" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019ba3f3-56dc-7a89-b3c1-7e111ba1ce1b" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019ba3f3-56dc-72f8-ad5e-6d3f07f2bc76" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_Security12bTitle_019ba3f3-56dc-72f8-ad5e-6d3f07f2bc76" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019ba3f3-56dc-7841-909d-11145babf8b0" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_TradingSymbol_019ba3f3-56dc-7841-909d-11145babf8b0" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019ba3f3-56dc-7098-a459-10489df15001" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_SecurityExchangeName_019ba3f3-56dc-7098-a459-10489df15001" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019ba3f3-56dc-7bae-b8da-e094ce3ab898" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityEmergingGrowthCompany_019ba3f3-56dc-7bae-b8da-e094ce3ab898" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine2_019ba3f3-56dc-7adf-b307-57572cb88fda" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressAddressLine2_019ba3f3-56dc-7adf-b307-57572cb88fda" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine3_019ba3f3-56dc-7d77-a2ba-cc1efabb30dd" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityAddressAddressLine3_019ba3f3-56dc-7d77-a2ba-cc1efabb30dd" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019ba3f3-56dc-7eaf-9c51-7828b499abe0" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_EntityCentralIndexKey_019ba3f3-56dc-7eaf-9c51-7828b499abe0" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019ba3f3-56dc-74f5-8c67-c1ef7d2926ea" 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_019ba3f3-56db-73f4-9b2d-af90f61b8f2a" xlink:to="loc_dei_AmendmentFlag_019ba3f3-56dc-74f5-8c67-c1ef7d2926ea" xlink:type="arc" order="23"/>
  </link:definitionLink>
</link:linkbase>
