EXHIBIT 23.1

              CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTANTS

We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3) and related Prospectus of Lexicon Genetics
Incorporated and to the incorporation by reference therein of our report dated
February 12, 2004, with respect to the consolidated financial statements of
Lexicon Genetics Incorporated included in its Annual Report (Form 10-K) for the
year ended December 31, 2003, filed with the Securities and Exchange Commission.

/s/ ERNST & YOUNG LLP

Houston, Texas
January 18, 2005