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                              [DELTAGEN LETTERHEAD]

                                                            EXHIBIT 10.14

15 March 2000

Dr. Pierre Chambon
The Association for Research at IGBMC
1, rue Laurant Fries
67404 ILLKIRCH
C.U. de Strasbourg, FRANCE

Dear Professor Chambon:

     We are pleased to present you with this letter confirming the basic
terms on which we are engaging IGBMC to provide consulting and other services
to Deltagen. The basic terms are as follows:

     -    The area of consultation and research is functional genomics,
          particularly knockout animal and gene disruption technologies.
          Deltagen will identify projects to be performed within the area of
          consultation and research, with the specific details (objectives,
          milestones, timetable, etc.) of individual projects to be jointly
          agreed in writing.

     -    The consultation period will be three (3) years, starting the date
          of commencement of the first project, renewable by mutual agreement.

     -    The work on each project will be undertaken at IGBMC by you and
          persons under your supervision and direction. The division of costs
          and expenses between Deltagen and IGBMC for each project will be
          negotiated in good faith.

     -    Deltagen will own the results and the intellectual property rights
          of each project, unless the written project documents specifically
          provide otherwise.

     -    The consideration to IGBMC for these consulting services and
          projects is the granting (subject to board approval) of a three (3)
          year warrant to purchase 400,000 shares of the Series C Preferred
          Stock of Deltagen, at an exercise price of US$3.58 per share. The
          warrant will vest in its entirety on the four (4) month anniversary
          of the commencement date of the first project, and may be exercised
          only after such vesting date. The warrant will expire on the three
          (3) year anniversary of the commencement date of the first project.
          The vesting schedule is:

          ----------------------------------------------------------------------
          TIME PERIOD                                  PERCENTAGE VESTED

          ----------------------------------------------------------------------
          Until four months after the commencement            0%
          date of the first project

          ----------------------------------------------------------------------
          At such four month anniversary date                100%

          ----------------------------------------------------------------------


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     Complete documentation, including a warrant instrument, confidentiality
agreement and detailed consulting agreement will be forthcoming. In the
interim, however, this letter will be our binding agreement. We are looking
forward to a mutually successful relationship with you. Please acknowledge
that this letter accurately sets forth our agreement by signing and returning
a copy of this letter by fax to us.



Sincerely,



  /s/ William Matthews/by Robert J. Discroll
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William Matthews




  /s/ Pierre Chambon                                     Date:   03/17/00
-----------------------------------                           ---------------
Pierre Chambon


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