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Exhibit 4.9       Agreement, dated March 23, 2001, between Gemini Genomics UK
                  Limited and CuraGen Corporation


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                               DATED 23 MARCH 2001






                           GEMINI GENOMICS UK LIMITED

                                       AND

                               CURAGEN CORPORATION


                        ---------------------------------
                                    AGREEMENT

                        RELATING TO PROVISION OF SAMPLES
                        ---------------------------------






                                 ARNOLD & PORTER
                                    TOWER 42
                               25 OLD BROAD STREET
                                 LONDON EC2N 1HO


            Confidential Treatment Requested and the Redacted Material
                has been separately filed with the Commission.
<PAGE>


                                TABLE OF CONTENTS

<TABLE>
<CAPTION>

                                                                     Page No.
                                                                     --------
<S>                                                                  <C>
1.   DEFINITIONS AND INTERPRETATION........................................3

2.   PROVISION OF DNA SAMPLES..............................................7

3.   FEES..................................................................7

4.   INTELLECTUAL PROPERTY.................................................7

5.   WARRANTIES, LIABILITY AND INDEMNITY...................................8

6.   CONFIDENTIALITY.......................................................8

7.   MISCELLANEOUS........................................................10

</TABLE>


                                       2
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                                    AGREEMENT

THIS AGREEMENT is made the 23d day of March 2001

BETWEEN:

(1)      GEMINI GENOMICS UK LIMITED whose principal place of business is at 162
         Science Park, Milton Road, Cambridge CB4 OGH ("Gemini"); and

(2)      CURAGEN CORPORATION whose principal place of business is at 555 Long
         Wharf Drive, New Haven, CT, USA ("CuraGen").

WHEREAS:

(A)      Gemini has collected a broad range of DNA and clinical data from human
         populations across certain disease areas which can be used to identify
         variations to specific genes and to determine the clinical relevance of
         genes with unknown function.

(B)      CuraGen wishes to obtain certain DNA samples and associated clinical
         data from Gemini and Gemini has agreed to provide such samples on the
         terms set out herein.

WHO HAVE AGREED AS FOLLOWS:

DEFINITIONS AND INTERPRETATION

1.       DEFINITIONS AND INTERPRETATION

         1.1     In this Agreement and in the Schedules to this Agreement the
                 following words and phrases shall have the following meanings
                 unless the context requires otherwise.

                 1.1.1     "AFFILIATE" - any company, partnership or other
                           entity which directly or indirectly Controls, is
                           Controlled by or is under common Control with, either
                           Party including as a Subsidiary or Holding Company;

                 1.1.2     "AGREEMENT" - this agreement and any and all
                           schedules, appendices and other addenda to it as may
                           be varied from time to time in accordance with the
                           provisions of this Agreement;

                 1.1.3     "[***] SAMPLES" - the DNA Samples derived from [***]
                           twins with a [***] as set out in Schedule 1;

                 1.1.4     "BUSINESS DAY" - 9.30 am to 5.30 pm on a day other
                           than a Saturday, Sunday, bank or other public holiday
                           in England and Wales or the USA;

                 1.1.5     "CLINICAL DATA" - the phenotypic data in Gemini's
                           possession and control in each case relating to the
                           [***] Samples or the [***] Samples and provided by
                           Gemini to CuraGen pursuant to Clause 2


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                           including, without limitation, the data described on
                           Schedules I and 2 attached hereto;

                 1.1.6     "COMPETENT AUTHORITY" - any local or national agency,
                           authority, department, inspectorate, minister,
                           ministry official or public or statutory person
                           (whether autonomous or not) of or of any government
                           of any country having jurisdiction over the Agreement
                           or any of the Parties or over the development or
                           marketing of medicinal products including the
                           European Commission, The Court of first instance and
                           the European Court of Justice;

                 1.1.7     "CONFIDENTIAL INFORMATION" - any trade secrets, Know
                           How, intellectual property rights or confidential
                           information relating to the business affairs or
                           finances of one of the other Parties supplied or
                           otherwise made available or coming into their
                           possession in relation to this Agreement (it being
                           understood that the Sample Results shall be
                           Confidential Information of CuraGen for purposes of
                           this Agreement);

                 1.1.8     "CONTROL" - means the ownership of more than 50% of
                           the issued share capital or the legal power to direct
                           or cause the direction of the general management and
                           policies of the Party in question;

                 1.1.9     "DNA SAMPLES" - those clinical samples of human DNA
                           in Gemini's possession and control which are provided
                           by Gemini pursuant to Clause 2;

                 1.1.10    "DOCUMENTS" - paper, notebooks, books, files,
                           ledgers, records, tapes, discs, diskettes, CDROM and
                           any other media on which Know How can be permanently
                           stored or recorded;

                 1.1.11    "FORCE MAJEURE" - in relation to any Party any event
                           or circumstance which is beyond the reasonable
                           control of that Party which event that Party could
                           not reasonably be expected to have taken into account
                           at the date of this Agreement and which results in or
                           causes the failure of that Party to perform any or
                           all of its obligations under this Agreement including
                           act of God, lightning, fire, storm, flood,
                           earthquake, accumulation of snow or ice, lack of
                           water arising from weather or environmental problems,
                           strike, lockout or other industrial disturbance, act
                           of the public enemy, war declared or undeclared,
                           threat of war, terrorist act, blockade, revolution,
                           riot insurrection, civil commotion , public
                           demonstration, sabotage, act of vandalism prevention
                           from or hindrance in obtaining in any materials,
                           energy or other supplies, explosion, fault or failure
                           of plant or machinery (which could not have been
                           prevented by Good Industry Practice), governmental
                           restraint, act of legislature and directive or
                           requirement of a Competent Authority governing either
                           Party provided that lack of


                                       4
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                           funds shall not be interpreted as a cause beyond the
                           reasonable control of that Party;

                 1.1.12    "KNOW HOW" -  unpatented technical and other
                           information which is not in the public domain
                           including, ideas, concepts, inventions, discoveries,
                           data, formulae, specifications, information relating
                           to material, procedures for experiments and tests and
                           results of experimentation and testing, results or
                           research development including laboratory records,
                           clinical trial data, case report forins, data
                           analyses, reports or summaries and information
                           contained in submissions to and information from
                           ethical committees and Competent Authorities;

                 1.1.13    "MATERIAL" - Documents and any chemical or biological
                           substances including any:-

                           (a) organic or inorganic element or compound;

                           (b) nucleotide or nucleotide sequence including DNA
                               and RNA sequence;

                           (c) gene;

                           (d) vector or construct including plasmids, phages or
                               viruses;

                           (e) host organism including bacteria, fungi, algae,
                               protozoa and hybridomas;

                           (f) eukaryotic or prokaryotic cell line or expression
                               system or any development strain or product of
                               that cell line or expression system;

                           (g) protein including any peptide or amino acid
                               sequence, enzyme, antibody or protein conferring
                               target properties and any fragment of a protein
                               or a peptide enzyme or antibody;

                           (h) drug or pro-drug;

                           (i) assay or reagent; or any other genetic or
                               biologic material or micro-organism;
                               multi-cellular plants;

                           (j) data for the derivation of molecular structures
                               including NMR spectra, X Ray diffraction
                               patterns, and other primary experimental
                               information, assignments and other calculations,
                               required for determination of the structure, and
                               co-ordinates of the derived molecular structure;

                           (k) computer programmes or algorithms.

                 1.1.14    "[***] SAMPLES" - the DNA Samples derived from [***]
                           case and control subjects;


                                       5
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                 1.1.15    "PARTIES" - Gemini and CuraGen and "PARTY" means
                           either of them;

                 1.1.16    "PATENT RIGHTS" - patent applications or patents,
                           author certificates, inventor certificates, utility
                           certificates, improvement patents and models and
                           certificates of addition and all foreign counterparts
                           of them and includes any divisions, renewals,
                           continuations, continuations-in-part, extensions,
                           reissues, substitutions, confirmations,
                           registrations, revalidation or additions of or to
                           them, as well as any supplementary protection
                           certificate in respect of them;

                 1.1.17    "SAMPLE RESULTS" - any and all results (including,
                           without limitation, all Patent Rights, Know-How and
                           Material) which are created, conceived or reduced to
                           practice by CuraGen during the term of this
                           Agreement through its use of the Samples and/or the
                           Clinical Data;

                 1.1.18    "SAMPLES" - the [***] of each of the [***] Samples
                           and the [***] Samples;

                 1.1.19    "SUBSIDIARY OR HOLDING COMPANY" - shall have the
                           meaning ascribed to those expressions by Section 736
                           of the Companies Act 1985 (as amended);

1.2              In this Agreement:-

                 1.2.1     unless the context otherwise requires all references
                           to a particular Clause, paragraph or Schedule shall
                           be a reference to that Clause, paragraph or Schedule,
                           in or to this Agreement as it may be amended from
                           time to time pursuant to this Agreement;

                 1.2.2     the table of contents and headings are inserted for
                           convenience only and shall be ignored in construing
                           this Agreement;

                 1.2.3     unless the contrary intention appears words importing
                           the masculine gender shall include the feminine and
                           vice versa and words in the singular include the
                           plural and vice versa;

                 1.2.4     unless the contrary intention appears words denoting
                           persons shall include any individual, partnership,
                           company, corporation, joint venture, trust,
                           association, organisational or other entity, in each
                           case whether or not having separate legal
                           personality;

                 1.2.5     reference to the words "include" or "including" are
                           to be construed without limitation to the generality
                           of the preceding words; and

                 1.2.6     reference to any statute or regulation includes any
                           modification or re-enactment of that statute or
                           regulation.


                                       6
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2.       PROVISION OF DNA SAMPLES

         2.1    By [***] Gemini shall provide CuraGen with the Samples and
                associated Clinical Data relating to the Samples.

         2.2    CuraGen shall use the Samples for determining the clinical
                relevance of genes only and shall not use the Samples for the
                production or sale of any products or for any clinical use or
                any use in humans. For the avoidance of doubt, CuraGen may use
                the Sample Results without restriction.

         2.3    The provision of the Samples and associated Clinical Data by
                Gemini to CuraGen pursuant to this Agreement shall be subject to
                any applicable legal and/or regulatory requirements.

         2.4    The Samples and associated Clinical Data shall be kept in a
                secure environment at CuraGen's premises. CuraGen shall use
                commercially reasonable efforts to protect the Samples and
                associated Clinical Data against theft, damage, loss, misuse
                and/or unauthorised access.

         2.5    CuraGen will not permit the Samples or associated Clinical Data
                to come into the possession or control of any person other than
                employees, agents, directors, consultants or professional
                advisors of CuraGen who are bound in writing to obligations
                comparable to those set forth in Clause 6.

         2.6    In handling the Samples, CuraGen shall comply with all local
                laws and requirements.

         2.7    The Samples are provided by Gemini to CuraGen on a non-exclusive
                basis and Gemini shall be free to use and to supply to third
                parties such quantities of any samples (including samples from
                the same set of individuals from whom the Samples are derived)
                as Gemini may in its sole discretion decide.

3.       FEES

         3.1    In consideration of the provision of the Samples pursuant to
                Clause 2, CuraGen shall pay to Gemini a fee of US [***] per
                Sample. CuraGen shall pay the fees per sample within fourteen
                (14) days of receipt of the Samples and associated Clinical Data
                supported by an appropriately detailed invoice from Gemini

         3.2    Payments to Gemini under this Agreement shall be made by
                electronic transfer to such bank account of Gemini as Gemini may
                notify to CuraGen.

4.       INTELLECTUAL PROPERTY

         4.1    Any and all Sample Results generated by CuraGen shall vest in
                and be owned by CuraGen.


                                       7
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         4.2    Gemini shall at the request of the CuraGen execute all documents
                and do all other acts and things as may be reasonably required
                in order to vest fully and effectively all rights in and to the
                Sample Results in CuraGen.

         4.3    Except as expressly set out herein no rights or licenses are
                granted by either Party hereunder.

5.       WARRANTIES, LIABILITY AND INDEMNITY

         5.1    Each Party represents and warrants to the other Party that:

                5.1.1  it has legal power, authority and right to enter into
                       this Agreement and to perform its respective obligations
                       in this Agreement; and

                5.1.2  it is not at the date of this Agreement a party to any
                       agreement, arrangement or understanding with any third
                       party which in any significant way prevents it from
                       fulfilling any of its material obligations under the
                       terms of this Agreement.

                5.1.3  Gemini hereby represents and warrants to CuraGen:

                       5.1.3.1     that the Clinical Data contains the
                                   information on Schedule I or 2 for each
                                   patient providing DNA Samples and

                       5.1.3.2.    that it has obtained, and will continue to
                                   obtain, informed consent from all patients
                                   and human subject volunteers that provide
                                   Clinical Data and materials and/or samples
                                   comprising the DNA Samples.

         5.2    Except as is expressly stated herein no other representation,
                warranty is made or given by or on behalf of either Party. In
                particular, and without limitation, Gemini gives no warranty of
                merchantability or fitness for particular purpose or any
                guarantee or warranty of any kind express or implied in relation
                to the [***] Samples, the [***] Samples or the associated
                Clinical Data.

         5.3    Neither Party shall be liable to the other in contract, tort,
                negligence, breach of statutory duty or otherwise for any
                economic loss or other loss of turnover, profits, business or
                goodwill or any loss, damage, costs or expenses of any nature
                whatsoever incurred or suffered by the other or its Affiliates
                of an indirect or consequential nature arising out of or in
                connection with this Agreement.

6.       CONFIDENTIALITY

         6.1    Each of the Parties undertakes and agrees to:


                                       8
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                6.1.1  use the Confidential Information only for the purposes
                       envisaged under this Agreement and not to use the same
                       for any other purpose whatsoever;

                6.1.2  ensure that only those of its officers and employees who
                       are directly concerned with the carrying out of this
                       Agreement have access to the Confidential Information on
                       a strictly applied "need to know" basis and are informed
                       of the secret and confidential nature of it;

                6.1.3  keep the Confidential Information secret and confidential
                       and not directly or indirectly to disclose or permit to
                       be disclosed, make available or pen-nit to be made
                       available the same to any third party (save as provided
                       in Clause 6.3.5) for any reason without the prior written
                       consent of the disclosing Party;

                6.1.4  keep the Confidential Information separate at all times
                       from all other Know How which it may hold;

                6.1.5  clearly identify the Confidential Information as
                       confidential.

         6.2    Each Party agrees not to disclose any of the terms of this
                Agreement or its existence to any third party without the prior
                written consent of the other Party.

         6.3    The obligations of confidence referred to in Clause 6.1 shall
                not extend to any Confidential Information which:-

                6.3.1  is or becomes generally available to the public otherwise
                       than by reason of breach by a recipient Party of the
                       provisions of this Clause;

                6.3.2  is known to the recipient Party and is at its free
                       disposal (having been generated independently by the
                       recipient Party or a third party in circumstances where
                       it has not been derived directly or indirectly from the
                       disclosing Party's Confidential Information)prior to its
                       receipt from the disclosing Party provided that evidence
                       of such knowledge is furnished by the recipient Party to
                       the disclosing Party within 28 days of receipt of that
                       Confidential Information;

                6.3.3  is subsequently disclosed to the recipient Party without
                       obligations of confidence by a third party owing no such
                       obligations to the disclosing Party in respect of that
                       Confidential Information;

                6.3.4  is required by law to be disclosed (including as part of
                       any regulatory submission or approval process) and then
                       only when prompt written notice of this requirement has
                       been given to the disclosing Party so that it may, if so
                       advised, seek appropriate relief to prevent such
                       disclosure provided always that in such circumstances
                       such disclosure shall be only to the extent so required
                       and shall be subject to prior consultation with the
                       disclosing Party with a view to agreeing timing and
                       content of such disclosure; or


                                       9
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                6.3.5  is disclosed to any Affiliate or the employees,
                       directors, agents, consultants and professional advisors
                       of the recipient Party, provided that such persons are
                       bound in writing to the obligations of confidentiality
                       set forth in this Clause 6;.

         6.4    All Confidential Information disclosed by the disclosing Party
                to the recipient Party shall remain the property of the
                disclosing Party. In the event that a court or Competent
                Authority assumes partial or complete control over the assets of
                a recipient Party based on the Insolvency Event of that Party,
                the recipient Party shall:

                6.4.1  promptly notify such court or Competent Authority:

                       (a)   that Confidential Information received from the
                             disclosing Party under this Agreement remains the
                             property of the Disclosing Party; and

                       (b)   of the confidentiality obligations under this
                             Agreement; and

                6.4.2  to the extent permitted by law, take all steps necessary
                       or desirable to maintain the confidentiality and security
                       of the disclosing Party's Confidential Information and to
                       ensure that the court or Competent Authority maintains
                       that Confidential Information in confidence in accordance
                       with this Agreement.

         6.5    The obligations of the Parties under Clause 6.1 to 6.4 shall
                survive for a period of five (5) years from the date of this
                Agreement.

7.       MISCELLANEOUS

         7.1    Neither Party shall without the prior written consent of the
                other, such consent not to be unreasonably withheld, assign the
                benefit and/or burden of this Agreement to any third party other
                than an Affiliate.

         7.2    If a Party is unable to perform any of its obligations under
                this Agreement due to an event of Force Majeure, such Party
                shall be excused such performance (but only such performance)
                during the period of such Force Majeure event.

         7.3    The validity, construction and interpretation of this Agreement
                and any determination of the performance which it requires shall
                be governed by English law. All disputes between the Parties
                arising out of the circumstances and relationships contemplated
                by this Agreement including disputes relating to the validity,
                construction or interpretation of this Agreement, and including
                disputes relating to pre-contractual representations which
                result in any action or proceedings, shall be subject to the
                exclusive jurisdiction of the English Courts.

         7.4    Except as expressly provided in this Agreement nothing herein
                deprives either Party or constitutes a waiver by either Party of
                any of its rights or remedies under common law, statute or
                otherwise.


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         7.5    This Agreement constitutes the entire agreement and
                understanding between the Parties and supersedes all prior oral
                or written understandings, arrangements, representations or
                agreements between them relating to the subject matter of this
                Agreement provided that this does not remove any right of action
                by either Party in respect of any fraudulent misrepresentation,
                fraudulent concealment or other fraudulent action.

         7.6    All formal notices to be given pursuant to this agreement shall
                be in writing and shall be delivered by hand, post or facsimile
                to the address of the Parties set out above (or such other
                address as may be notified by a Party to the other from time to
                time in accordance with this Clause) and in the case of a
                facsimile with a confirmation copy being sent by post. Notices
                shall be deemed to have been received:

                7.6.1    if delivered by courier, at the time of delivery;

                7.6.2    if sent by post:

                         (a)   where posted in the country of the addressee,
                               on the second  working day following the day of
                               posting; and

                         (b)   where posted in any other country, on the fifth
                               working day following the day of posting;

                7.6.3    if sent by facsimile, on acknowledgement by the
                         recipient facsimile receiving equipment on a Business
                         Day if the acknowledgement occurs before 1700 hours
                         local time on a Business Day of the recipient and in
                         any other case on the following Business Day.

         7.7    The activities of the Parties contemplated pursuant to this
                Agreement shall not constitute a partnership and neither Party
                is the agent of the other Party or has the authority to bind the
                other Party in any way except as provided in this Agreement.

         7.8    Each Party shall bear its own legal costs and other expenses
                incurred in the negotiation, preparation, execution and
                implementation of this Agreement.

         7.9    Any press releases to be made by either Party relating to this
                Agreement will require the approval of the other Party.

         7.10   This Agreement may be executed in any number of counterparts and
                by the Parties by separate counterparts, each of which when so
                executed shall be an original and all of which shall constitute
                one and the same instrument.

         7.11   The operation of the Contract (Rights of Third Parties) Act 1999
                is hereby expressly excluded save that the Parties acknowledge
                and agree that Affiliates of either Party may enforce against
                the Parties (and a person who is the lawful successor to or a
                permitted assignee of the rights of a Party) the rights and
                benefits under this Agreement in accordance with that Act.


                                       11
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IN WITNESS WHEREOF the Parties have executed this document the day and year
first above written.

SIGNED by
for and on behalf of
GEMINI GENOMICS UK LIMITED
in the presence of:

SIGNED by
for and on behalf of
CURAGEN CORPORATION
in the presence of:


                                       12
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                                   SCHEDULE 1

                        [***] SAMPLES AND PHENOTYPIC DATA


                                       13
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                                   SCHEDULE 2

                        [***] SAMPLES AND PHENOTYPIC DATA


                                       14