<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <!-- Generated by Workiva -->
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001944119</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001818331</issuerCik>
      <issuerName>GeneDx Holdings Corp.</issuerName>
      <secFileNumber>001-39482</secFileNumber>
      <issuerAddress>
        <com:street1>333 Ludlow St, North Tower</com:street1>
        <com:street2>6th Floor</com:street2>
        <com:city>Stamford</com:city>
        <com:stateOrCountry>CT</com:stateOrCountry>
        <com:zipCode>06902</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>888-729-1206</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Kevin Feeley</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Morgan Stanley Smith Barney</name>
        <address>
          <com:street1>2000 Westchester Avenue</com:street1>
          <com:city>Purchase</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10577-2530</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>5009</noOfUnitsSold>
      <aggregateMarketValue>363400</aggregateMarketValue>
      <noOfUnitsOutstanding>28588943</noOfUnitsOutstanding>
      <approxSaleDate>06/09/2025</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <acquiredDate>06/09/2025</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Unit Vest</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1266</amountOfSecuritiesAcquired>
      <paymentDate>06/09/2025</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <acquiredDate>06/16/2025</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Unit Vest</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>3743</amountOfSecuritiesAcquired>
      <paymentDate>06/16/2025</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>03/10/2025</saleDate>
      <amountOfSecuritiesSold>922</amountOfSecuritiesSold>
      <grossProceeds>87300</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>03/13/2025</saleDate>
      <amountOfSecuritiesSold>402</amountOfSecuritiesSold>
      <grossProceeds>36200</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>03/17/2025</saleDate>
      <amountOfSecuritiesSold>3749</amountOfSecuritiesSold>
      <grossProceeds>362600</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>03/26/2025</saleDate>
      <amountOfSecuritiesSold>8746</amountOfSecuritiesSold>
      <grossProceeds>836200</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>04/09/2025</saleDate>
      <amountOfSecuritiesSold>14270</amountOfSecuritiesSold>
      <grossProceeds>1313700</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>04/29/2025</saleDate>
      <amountOfSecuritiesSold>388</amountOfSecuritiesSold>
      <grossProceeds>43900</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin Feeley</name>
        <address>
          <com:street1>333 Ludlow St, North Tower</com:street1>
          <com:street2>6th Floor</com:street2>
          <com:city>Stamford</com:city>
          <com:stateOrCountry>CT</com:stateOrCountry>
          <com:zipCode>06902</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Class A Common Stock</securitiesClassTitle>
      <saleDate>06/02/2025</saleDate>
      <amountOfSecuritiesSold>370</amountOfSecuritiesSold>
      <grossProceeds>26400</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>Represents 5,009 shares to be sold on behalf of the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units, including: 1) 1,266 shares to be sold in connection with the vesting of restricted stock units on June 9, 2025; and 2) 3,743 shares to be sold in connection with the vesting of restricted stock units on June 16, 2025. Shares sold in the past 3 months by the Reporting Person include: 1) 14,577 shares sold to cover tax withholding obligations in connection with the vesting and settlement of RSUs; and 2) 14,270 shares in connection with sales pursuant to the Reporting Person's Rule 10b5-1 trading plan adopted on August 21, 2024.</remarks>
    <noticeSignature>
      <noticeDate>06/09/2025</noticeDate>
      <signature>/s/ Kevin Feeley</signature>
    </noticeSignature>
  </formData>
</edgarSubmission>
