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                                                            EXHIBIT NO. 10.47



   Confidential Materials omitted and filed separately with the Securities and
             Exchange Commission. Asterisks denote such omissions.



GENE   LOGIC
                                                                   HEADQUARTERS
                                                                Gene Logic Inc.
                                                        708 Quince Orchard Road
                                                   Gaithersburg, Maryland 20878
                                                        Telephone: 301.987.1700
                                                        Facsimile: 301.987.1701
                                                            www. genelogic. com
December 27, 2001
                                                               Gene Logic, Inc.
                                                  2001 Center Street, Suite 600
                                                      Berkley, California 94704
                                                        Telephone: 510.981.3144
                                                        Facsimile: 510.649.3449
Genaissance Pharmaceuticals, Inc.
5 Science Park
New Haven, CT 06511
Attention: Kevin Rakin,
           President and Chief Financial Officer

Re:  Collaboration  Agreement (the "Agreement") dated June 28, 2000 between GENE
     LOGIC INC. ("Gene Logic") and GENAISSANCE PHARMACEUTICALS, INC.
     ("Genaissance")

Dear Kevin:

As we discussed, this binding letter agreement (the "AMENDMENT") will confirm
our understanding regarding the amendment of the Agreement. Capitalized terms
used but not defined herein shall have the meanings provided in the Agreement.
Gene Logic and Genaissance hereby agree as follows:

1. Notwithstanding any provision of the Agreement to the contrary, "ACCESS TERM"
shall mean the period commencing on the Effective Date and continuing until
December 31, 2002, subject to termination or extension as set forth in the
Agreement, as amended by this Amendment.

2. Section 6.1 of the Agreement is hereby amended and restated to read in its
entirety as follows:

     (a)  "GeneExpress(R) Product Access Fees. GeneExpress(R) Product fees will
          be paid by Genaissance to cover (i) the initial and ongoing Access to
          the GeneExpress(R) Product, (ii) all GeneExpress(R) Product content
          updates and (iii) continuous upgrades and releases


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          of Gene Logic Software. The GeneExpress(R) Product fee for the period
          commencing on the Effective Date and continuing until [**] shall be
          $[**]; the GeneExpress(R) Product fee for the period commencing on
          [**] and continuing until [**] shall be $[**]; the GeneExpress(R)
          Product fee for the period commencing on [**] and continuing until
          [**] shall be $[**]; and the GeneExpress(R) Product fee for the
          period commencing [**] and continuing until expiration of the
          Access Term shall be $[**].

     (b)  The GeneExpress(R) Product fees for the period commencing [**]
          and continuing until expiration of the Access Term shall be
          payable quarterly, in arrears, in accordance with SCHEDULE A attached
          hereto. For purposes of clarity, the Parties acknowledge that the
          payment obligations under this Section shall remain subject to the
          provisions of Section 9.2 (dealing with early termination of the
          Agreement in the event of breach) and Section 9.5 (dealing with early
          termination of the Agreement in the event of bankruptcy).

     (c)  The GeneExpress(R)Product fee for the period commencing on [**]
          and continuing until December 31, 2001 shall be paid on [**]."

3. For purposes of clarity, the Parties acknowledge that the GeneExpress(R)
Product Fees for the period commencing on the Effective Date and continuing
until [**] have already been paid.

4. Section 6.3 of the Agreement is hereby amended and restated to read in its
entirety as follows:

     (a)  "SNP Data Access Fees. SNP Data fees will be paid by Gene Logic to
          cover (i) the initial and ongoing access to the SNP Data, and (ii) all
          SNP Data content updates. The SNP Data fee for the period commencing
          on the Effective Date and continuing until [**] shall be $[**]; the
          SNP Data fee for the period commencing on [**] and continuing until
          [**] shall be $[**]; the SNP Data fee for the period commencing on
          [**] and continuing until [**] shall be $[**]; and the SNP Data fee
          for the period commencing [**] and continuing until expiration of the
          Access Term shall be $[**].

     (b)  The SNP Data fees for the period commencing [**] and continuing until
          expiration of the Access Term shall be payable quarterly, in arrears,
          in accordance with SCHEDULE B attached hereto. For purposes of
          clarity, the Parties acknowledge that the payment obligations under
          this Section shall remain subject to the provisions of Section 9.2.
          (dealing with early termination of the Agreement in the event of
          breach) and Section 9.5 (dealing with early termination of the
          Agreement in the event of bankruptcy).

     (c)  The SNP Data fee for the period commencing on [**] and continuing
          until [**] shall be paid on [**]."

5. For purposes of clarity, the Parties acknowledge that the SNP Data fees for
the period commencing on the Effective Date and continuing until [**] have
already been paid.

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6. Section 9.1 of the Agreement is hereby amended and restated to read in its
entirety as follows:

                  "Unless earlier terminated in accordance with this Article 9,
                  the term of this Agreement shall begin on the Effective Date
                  and continue until the expiration of the Access Term, or such
                  longer period of time as the Parties may agree in writing."

7. Sections 9.3 and 9.4 of the Agreement are hereby deleted in their entirety
and shall be of no further force or effect.

8. Unless this Agreement has been terminated in accordance with Article 9 (as
amended by this Amendment) prior to [**], then, on or promptly after [**],
the Parties shall commence good faith negotiations regarding the terms upon
which the Access Term may be extended. Any such extension of the Access Term
shall be pursuant to a written agreement executed by the Parties. The Parties
acknowledge that neither Party shall be obligated to extend the Access Term
beyond December 31, 2002.

9. Upon the execution and delivery of this Amendment by Genaissance and Gene
Logic, (a) Genaissance shall be deemed to have rescinded its Notice of
Termination of Collaboration Agreement, dated December 13, 2001 (the "Notice"),
and (b) the Parties agree that the Notice shall have no further force or effect.

Except as specifically amended by this Amendment, the terms and conditions of
the Agreement shall remain in full force and effect. This Amendment may be
executed in two or more counterparts, each of which shall be deemed an original,
but all of which together shall constitute one and the same instrument.

If the foregoing is acceptable to you, please sign and date this Amendment in
the space provided below and return it to me.

                                      Sincerely,


                                      GENE LOGIC INC.


                                      By: /S/LARRY TIFFANY
                                         ------------------------
                                         Larry Tiffany
                                         Vice President of Business Development


AGREED TO AND ACCEPTED THIS 27TH DAY OF DECEMBER, 2001:

GENAISSANCE PHARMACEUTICALS, INC.


By: /S/ KRISHNAN NANDABALAN
   --------------------------
Krishnan Nandabalan
Vice President, Alliances



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                                   SCHEDULE A

               Payment Schedule for GeneExpress(R) Product Fees -
                               [**] through [**]

                   Date Due                   Amount of Payment
                   [**]                             $[**]
                   [**]                             $[**]
                   [**]                             $[**]
                   [**]                             $[**]
                   [**]                             $[**]






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                                   SCHEDULE B

                      Payment Schedule for SNP Data Fees --
                                [**] through [**]


                   Date Due                   Amount of Payment
                   [**]                             $[**]
                   [**]                             $[**]
                   [**]                             $[**]
                   [**]                             $[**]
                                                    $[**]