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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001062822-04-000063.txt : 20041229
<SEC-HEADER>0001062822-04-000063.hdr.sgml : 20041229
<ACCEPTANCE-DATETIME>20041229163615
ACCESSION NUMBER:		0001062822-04-000063
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041228
FILED AS OF DATE:		20041229
DATE AS OF CHANGE:		20041229

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GREGORY JULIA P
		CENTRAL INDEX KEY:			0001226675

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30111
		FILM NUMBER:		041231495

	MAIL ADDRESS:	
		STREET 1:		8800 TECHNOLOGY FOREST PLACE
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77381

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LEXICON GENETICS INC/TX
		CENTRAL INDEX KEY:			0001062822
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		IRS NUMBER:				760474169
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		8800 TECHNOLOGY FOREST PLACE
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77381
		BUSINESS PHONE:		2818633000

	MAIL ADDRESS:	
		STREET 1:		8800 TECHNOLOGY FOREST PLACE
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77381
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>gre225.xml
<TEXT>
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        <issuerName>LEXICON GENETICS INC/TX</issuerName>
        <issuerTradingSymbol>LEXG</issuerTradingSymbol>
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            <rptOwnerName>GREGORY JULIA P</rptOwnerName>
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        <reportingOwnerAddress>
            <rptOwnerStreet1>8800 TECHNOLOGY FOREST PLACE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>THE WOODLANDS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>773811160</rptOwnerZipCode>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>EVP, Corp Dev and CFO</officerTitle>
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            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2004-12-29</value>
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            <deemedExecutionDate></deemedExecutionDate>
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                    <value>By Family Trusts for Minor Children</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>700</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>7.61</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4247.00</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
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                    <value>By Family Trusts for Minor Children</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <value>2004-12-28</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>300</value>
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                <transactionPricePerShare>
                    <value>7.62</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>3947.00</value>
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                    <value>By Family Trusts for Minor Children</value>
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                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
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                <transactionShares>
                    <value>100</value>
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                <transactionPricePerShare>
                    <value>7.64</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <securityTitle>
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                    <value>A</value>
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    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Gregory, Julia P.</signatureName>
        <signatureDate>2004-12-29</signatureDate>
    </ownerSignature>
</ownershipDocument>

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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----