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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   ----------

                                    FORM 8-K

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                                 CURRENT REPORT
     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

         DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): MAY 30, 2006

                          LEXICON GENETICS INCORPORATED
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

                                                       
            DELAWARE                                               76-0474169
(STATE OR OTHER JURISDICTION OF           000-30111             (I.R.S. EMPLOYER
 INCORPORATION OR ORGANIZATION)   (COMMISSION FILE NUMBER)   IDENTIFICATION NUMBER)



                          8800 TECHNOLOGY FOREST PLACE
                           THE WOODLANDS, TEXAS 77381
                         (ADDRESS OF PRINCIPAL EXECUTIVE
                              OFFICES AND ZIP CODE)

                                 (281) 863-3000
                         (REGISTRANT'S TELEPHONE NUMBER,
                              INCLUDING AREA CODE)

     Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligations of the registrant under any of the
following provisions:

[ ]  Written communications pursuant to Rule 425 under the Securities Act (17
     CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
     CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))

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ITEM 1.01 ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT

     On May 30, 2006, we entered into an amendment to our Collaboration and
License Agreement dated as of December 17, 2003 with Bristol-Myers Squibb
Company relating to the discovery, development and commercialization of small
molecule drugs in the neuroscience field. By way of the amendment, Bristol-Myers
Squibb exercised its option under the original agreement to extend the target
discovery portion of the alliance for an additional two years. Bristol-Myers
Squibb will provide us with $20 million in additional research funding over the
two-year extension, which begins in January 2007.

     The target discovery portion of the alliance encompasses the physiological
and behavioral analysis of genes to identify promising new neuroscience targets
for the development of small molecule drugs to treat disorders including
depression, anxiety, schizophrenia, pain and Alzheimer's disease. The extension
of the target discovery program term provides for further advanced research on
selected targets.



                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                        LEXICON GENETICS INCORPORATED


Date: June 1, 2006                      By: /s/ JEFFREY L. WADE
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                                            Jeffrey L. Wade
                                            Executive Vice President and
                                            General Counsel