SEC FORM 3

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

MCNAIR ROBERT C

(Last)

(First)

(Middle)

(Street)

(City)

(State)

(Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
07/10/2003

3. Issuer Name and Ticker or Trading Symbol
LEXICON GENETICS INC/TX [ LEXG ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
1. Title of Derivative Security (Instr. 4)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)

Explanation of Responses:

1. The reporting person is the sole limited partner of RCM Financial Services, L.P., and the sole director and stockholder of RCM Financial Services GP, Inc., which serves as the sole general partner of RCM Financial Services, L.P.

2. The reporting person is the sole limited partner of Palmetto Partners, Ltd., and the sole director and stockholder of Palmetto Capital Corporation, which serves as the sole general partner of Palmetto Partners, Ltd.

3. Palmetto Partners, Ltd. owns a 74% limited partner interest in Cogene Biotech Ventures, L.P. Palmetto Partners, Ltd. is the sole member of Cogene Biotech Ventures GP, L.L.C., which serves as the sole general partner of Cogene Biotech Ventures, L.P. The reporting person disclaims beneficial ownership of the securities held by Cogene Biotech Ventures, L.P., except to the extent of his pecuniary interest therein.

No securities are beneficially owned.

	Robert C. McNair	07/18/2003
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.