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EXHIBIT 10.15


                             CONFIDENTIAL TREATMENT

GENOMETRIX INCORPORATED HAS REQUESTED THAT THE MARKED PORTIONS OF THIS DOCUMENT
BE ACCORDED CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 UNDER THE SECURITIES ACT
OF 1933, AS AMENDED.

CONFIDENTIAL MATERIAL OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION. ASTERISKS DENOTE SUCH OMISSIONS.


                FIRST AMENDMENT TO LICENSE AND RESEARCH AGREEMENT

         This First Amendment, dated March 20, 2000 (the "Amendment"), is
between Motorola, Inc., a Delaware corporation and Genometrix Incorporated, a
Delaware corporation and amends that certain License and Research Agreement (the
"Agreement") between MOTOROLA and GENOMETRIX dated July 2, 1999.

                                   BACKGROUND

         MOTOROLA and GENOMETRIX desire to amend the Agreement to better
accommodate certain changes in the marketplace and to better reflect the
original intention of the parties.

         Accordingly, the parties agree as follows:

1. Definitions. All defined terms, unless assigned a specific meaning in this
Amendment, shall have the meaning set forth in the Agreement.

2. Sections 1.18 and 2.9. The term "*** *** format arrays" is deleted from
Section 1.18, the first sentence of Section 2.9, where the term is used twice,
and from the second sentence of Section 2.9, where the term is used once. In its
place, the term "*** ***** MICROARRAY" is substituted. In addition, the
following sentence is added at the end of Section 1.18:

"The term *** ***** MICROARRAY shall mean a device on which an array of
biomolecules have been or are intended to be immobilized (as in the case of a
blank array), whereby the biomolecules are immobilized in a ****** ******.

3. Section 2.1. As contemplated by Section 2.1, the parties shall extend the
SURFACE CHEMISTRIES RESEARCH PROGRAM until December 31, 2000. The parties shall
mutually agree upon an amended RESEARCH PLAN, a draft of which is attached as
Exhibit E-1. GENOMETRIX shall commit resources equivalent to at least ***** *
**** **** ********* employees to the SURFACE CHEMISTRIES RESEARCH PROGRAM for
the duration of the extended SURFACE CHEMISTRIES RESEARCH PROGRAM. MOTOROLA
shall pay GENOMETRIX ***** ******* ***** ******** ******* ******** for this
extension: *** ******* *** ***** ******** ******* ******** upon execution of
this Amendment and each of ****** * **** *** ******** ** ****; all subject to
the completion by GENOMETRIX of the relevant milestones set forth in the amended
RESEARCH PLAN.

4. Section 4. Section 4 is deleted in its entirely and replaced with the
following paragraph:
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"MOTOROLA agrees, beginning January 1, 2001 and subject to its capacity
constraints, to provide to GENOMETRIX **** ******* ****** (i.e. ****** ******
**** **** *** ******** ******) employing the SURFACE CHEMISTRIES technologies
developed by the extended SURFACE CHEMISTRIES RESEARCH PROGRAM ** *********
*****. GENOMETRIX shall have the right to use **** **** ******* ****** *** ***
******** ******** ********, *** ******** ******** ********** ** ** *********
******. The rights granted to GENOMETRIX in this Section 4 shall not be
transferred to a THIRD PARTY without the written permission of MOTOROLA. In
addition, MOTOROLA agrees to make GENOMETRIX * ********* ******** ** ********
********, and GENOMETRIX agrees to provide to MOTOROLA ******** ********, ****
** *** ****** ******* ********, ** ********* *******."

5. Section 6.2. The following sentence is added at the end of Section 6.2:

"Notwithstanding MOTOROLA'S obligation to pay royalties to GENOMETRIX on NET
SALES of LICENSED PRODUCTS sold by MOTOROLA or its SUBSIDIARIES and covered by a
VALID PATENT CLAIM set forth in this Section 6.2 or Section 6.5, the parties
agree that any LICENSED PRODUCTS sold by MOTOROLA employing E-FIELD MANIPULATION
IP that also encompass any *** ****** TECHNOLOGY shall bear a single royalty of
***** ******* ** of NET SALES. *** ****** TECHNOLOGY is defined as the
proprietary ******* technology developed by and/or licensed to ******** *****
******* *** * ********** *********** *** and is further defined in the
Intellectual Property Agreement dated ***** ** **** ******* ******** *** ***.
The sentences immediately preceding this sentence, together with Paragraph
6.3(b) below, shall be effective only upon the execution of agreements between
Motorola and *** ******* *** *********** GENOMETRIX E-FIELD MANIPULATION IP and
*** ****** ** ***** *** ****** *** ***** *** *********
********* ** *** ******** ** ********** * ***** *********** **."

6. Section 6.3. Section 6.3 is deleted in its entirety and the following
paragraph is substituted.

"6.3 In consideration of the rights and licenses granted hereunder, MOTOROLA
shall pay GENOMETRIX ***** ******* *** of any SUBLICENSE INCOME received by
MOTOROLA in consideration for the grant of a sublicense under the GENOMETRIX
PATENTS. The foregoing notwithstanding, (a) in all cases the percentage of
SUBLICENSE INCOME payable by MOTOROLA to GENOMETRIX in consideration for the
grant of a sublicense under the GENOMETRIX PATENTS shall be ***** ** ** *******
**** *** amount owed by GENOMETRIX to MIT pursuant to the MIT AGREEMENT; (b) in
the case of SUBLICENSE INCOME received by MOTOROLA **** ***, (i) SUBLICENSE
INCOME shall include only cash consideration paid by *** ** ******** as part of
the grant of the sublicense, including but not limited to up-front license fees,
running royalties, milestone payments or development payments, as set forth in
the actual sublicense agreement between *** *** ******* and (ii) in addition to
any cash consideration paid by *** ** ******* (of which GENOMETRIX shall be
entitled to ***** ****** ***, the percentage of running royalties to be paid by
MOTOROLA to


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GENOMETRIX on the NET SALES of E-FIELD PRODUCTS by *** ***** ** no less than ***
*** *** **** ****** *** of NET SALES of E-FIELD PRODUCTS by ***; and (c)
notwithstanding the foregoing and Exhibit F, in the event that MOTOROLA grants a
sublicense to ****** ** *** ******** for the field of E-FIELD MANIPULATION IP,
************* *** ****** ** *** ** ** ****** ****** ****** ****** **********
within ***** * ****** following the execution of this Amendment, MOTOROLA shall
pay to GENOMETRIX SUBLICENSE INCOME of a pre-paid license fee of ****** ******,
***** ******* *** ***** ******* ******* ********, and (ii) an annual running
royalty of the greater of ***** ** ** *** ***** ** ******** ******** ** *******
** ***** ******* ******* *** ******** ******* ********. MOTOROLA agrees to
provide GENOMETRIX with advance written notice of and a copy of any such
sublicense agreements."

6. All other terms of the Agreement remain unchanged.

   Authorized representatives of the parties have executed this Amendment.

Motorola, Inc.                                 Genometrix Incorporated

By: /s/ Nicholas Naclario                      By: /s/ Mitchell Eggers
    ---------------------                          -------------------
        Nicholas Naclario                              Mitchell D. Eggers, Ph.D.
Title:  Vice President and General Manager     Title:  Chief Executive Officer

By: /s/ Jonathan Meyer
    ------------------
        Jonathan Meyer
Title:  Senior Vice President,
        Assistant General Counsel,
        and Director of Patents, Trademarks and Licensing


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Exhibit E-1


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EXCHANGE COMMISSION. ASTERISKS DENOTE SUCH OMISSIONS.


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