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                                                                    EXHIBIT 23.1

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

      We consent to the incorporation by reference in the previously filed
Registration Statements on Form S-8 (Registration Nos. 333-41532 and 333-66380)
pertaining to the 2000 Equity Incentive Plan, the 2000 Non-Employee Directors'
Stock Option Plan and the Coelacanth Corporation 1999 Stock Option Plan and on
Form S-3 (Registration Nos. 333-67294 and 333-101549) and in the related
prospectus of Lexicon Genetics Incorporated, of our report dated February 13,
2003, with respect to the consolidated financial statements of Lexicon Genetics
Incorporated included in this Annual Report (Form 10-K) for the year ended
December 31, 2002.


                                                    /s/ ERNST & YOUNG LLP

Houston, Texas
March 14, 2003

