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                                                                    EXHIBIT 10.6

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS,
HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS AMENDED.

                            COLLABORATION AGREEMENT

    THIS AGREEMENT is dated the 16th of March, 2000 (the "Effective Date") and
is made between KIVA GENETICS, INC. ("KG"), a Delaware corporation, having its
principal place of business at 2375 Garcia Avenue, Mountain View, CA 94043; and
HEALTHEON/WEBMD CORPORATION ("WebMD") a Delaware corporation, having its
principal place of business at 400 The Lenox Building, 3399 Peachtree Road NE,
Atlanta, Georgia 30326.

                                    WHEREAS:

    A.  WebMD has expertise and experience in owning, controlling, directing,
promoting, and sponsoring one or more World Wide Web sites devoted to health and
health-related topics and directed to health care practitioners and consumers.

    B.  KG's principal business purpose in connection with this Agreement is to
promote and facilitate the conduct of research seeking to establish associations
between phenotypic data, including clinical courses, diagnoses, prognoses and
responses to therapy, with genetic and genomic data, which research includes the
recruitment of persons for the collection of DNA or RNA samples for the purpose
of discovering new genes and/or new utilities of genes, developing genetic-based
clinical management tools based on those associations to be used for medical
treatment, patient stratification and assistance in the development and
commercialization of new pharmaceutical, diagnostic, medical device and other
healthcare products and services (the "KG Business Purpose").

    C.  KG also intends to solicit blood samples from individuals who visit the
KG Site, which will be analyzed with respect to their genetic data and such
genetic data will be combined with the individual's own medical data entered at
the KG Site to build a database for use in determining the genetic component of
disease and treatment.

    D.  The parties wish to collaborate in the areas of marketing, technology,
competencies, Genetics and Genomics content access, and revenue sharing, as
specifically set forth herein.

                        IT IS HEREBY AGREED AS FOLLOWS:

1.  CERTAIN DEFINITIONS.

        1.1 "AFFILIATE" means an entity that controls, is controlled by, or is
    under common control with a Party hereunder, where "control" means the
    ownership of at least 50% of the stock of such entity or the ability to
    control the management decisions of such entity regardless of ownership
    percentage interest.

        1.2 "COMPETITIVE GENETICS AND GENOMICS COMPANY" means any third party
    entity whose primary business purpose is directly competitive with the KG
    Business Purpose, including without limitation, those entities set forth on
    Schedule 1.2.

        1.3 "GENETICS AND GENOMICS" means the study or analysis of an
    individual's DNA or RNA and the study of the human genome and variations
    therein for discovery research, clinical diagnostic and medical management.

        1.4 "KG CONTENT" means all content or information, in any medium,
    provided by KG for use of the WebMD Site, including without limitation any
    listing data, hyperlinks, text, music, sound, photographs, video, graphics,
    other data or software related to Genetics and Genomics, and,


[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
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EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

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    subject to Section 3.7, chats or moderated chats or any transcriptions
    thereof. The KG content will be scientifically sound and current and will
    fairly present all scientifically responsible points of view where
    appropriate to deliver a balanced expression of the current state of the
    genetic and genomic science and will be free of advertisement, infomercial
    or "advertorial" content. WebMD may at its own expense engage the services
    of one or more experts in the field of genetics and genomics to review the
    KG Content to determine its compliance with these standards.

        1.5 "WEBMD SITE" means the web site devoted to health issues and owned
    and operated by WebMD and accessible at www.webmd.com or its successor URL.

        1.6 "KG SITE" means the web site owned and to be launched and operated
    by KG following the Effective Date and accessible at www.kivagen.com or its
    successor URL, and any additional sites operated by or for KG (and KG
    Affiliates) and designated by KG (and KG Affiliates) in writing from time to
    time.

2.  CONTENT; EXCLUSIVITY; LICENSE TO USE.

        2.1 KG CONTENT. KG will create and deliver to WebMD the KG Content at
    its own cost. The KG Content shall be qualitatively and quantitatively
    comparable to other channels on the WebMD Site of a similar size and nature.

        2.2  DEDICATED CHANNEL.  Promptly following the Effective Date in
    accordance with a schedule mutually agreed to by the Parties, WebMD shall
    establish a channel dedicated to Genetics and Genomics (the "Consumer G&G
    Channel") on WebMD Health, which is the consumer oriented portion of the
    WebMD Site, and shall establish a channel dedicated to Genetics and Genomics
    (the "Professional G&G Channel") on WebMD Practice, which is the
    professional oriented portion of the WebMD Site. The Consumer G&G Channel
    and the Professional G&G Channel are sometimes collectively referred to as
    the "Channels."

        2.3  INTEGRATION OF KG CONTENT.  Subject to the terms of this Agreement,
    KG shall license KG Content to WebMD for use on the Channels as the Channels
    are delivered in the United States, and WebMD shall, where practicable,
    integrate the KG Content into other portions of the WebMD Site as the WebMD
    Site is delivered in the United States.

        2.4  EXCLUSIVITY.  KG shall be the exclusive provider of content related
    to Genetics and Genomics in the Channels during the Term hereof. Subject to
    the terms and conditions of this Agreement, WebMD agrees that, during the
    Term, it shall not enter into any agreement with any third party for the
    provision of Genetics and Genomics content for use in the Channels.
    Notwithstanding the foregoing, WebMD may include in the Channels
    (i) content that is not related to Genetics and Genomics; (ii) content that
    is originally generated by WebMD, provided it does not unreasonably
    duplicate the KG Content; and (ii) content from non-profit, academic and
    charitable sources, provided to WebMD without charge, in each case to the
    extent that KG is unable to provide such content on the Channels after
    notice from WebMD, but within the time frame reasonably required by WebMD
    under the circumstances. WebMD shall be free to include content related to
    Genetics and Genomics from any source on the WebMD Site outside of the
    Channels provided that WebMD shall not include content related to Genetics
    and Genomics from a Competitive Genetics and Genomics Company for the
    purpose of advancing a business purpose of such a company which is
    competitive with the KG Business Purpose during the Term. In addition WebMD
    agrees that it shall not establish or create a channel on the WebMD Site
    that is duplicative of either of the Channels. Moreover, such exclusivity
    shall not include iterations of the WebMD Site which are targeted to
    audiences outside the United States. WebMD agrees to use [*] WebMD [*] to
    enter into [*] with KG with respect to [*] (without the necessity of [*] by
    WebMD to such entities or any other entity). The KG Content shall include
    enough content and services as determined by WebMD in order to offer an
    appropriate channel related to Genetics and Genomics to users of the WebMD
    Site ("Users"). In additional, WebMD agrees that it shall not enter into any
    agreement after the Effective Date with any third party for the soliciation,
    by means of the WebMD Site, of the collection of human DNA or RNA samples
    for the KG Business Purpose.

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
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        2.5  LICENSE.  Pursuant to Paragraph 2.2, KG hereby grants, to WebMD,
    during the Term, a nonexclusive, nontransferable, worldwide, limited-scope
    license to use, copy, adapt and publish the KG Content in the Channels and
    the WebMD Site; store the KG Content on WebMD servers; and to distribute,
    perform and display the KG Content on or in conjunction with the WebMD Site
    and its various means of distribution, including broadband and wireless.
    WebMD shall further have the right to use the KG Content, or any portion
    thereof, to advertise, market and promote the inclusion of the same on the
    Channels or the WebMD Site and/or build traffic for the Channels or the
    WebMD Site. WebMD may modify the text of the KG Content as it deems
    necessary or appropriate, consistent with WebMD's exercise of its absolute
    rights of editorial and artistic discretion with respect to the Channels and
    the WebMD Site, but in a manner that preserves the underlying integrity and
    meaning of such content.

        2.6 KG acknowledges and intends that in the event any portion of the KG
    Content is content which [*] has the exclusive right to provide to WebMD
    pursuant to an agreement in effect on the Effective Date, as it may be
    amended from time to time, then WebMD shall not be required to display such
    KG Content (or portion thereof) in any manner that conflicts with the terms
    of such agreement, as amended.

        2.7 The parties acknowledge that KG is developing KG Content at its own
    cost and in tandem with the creation by WebMD of the Channels; provided
    however, WebMD's acknowledgement of KG's tandem development and creation
    shall not diminish any obligation of KG set forth hereunder. In addition to
    the circumstances set forth in Section 2.4 hereof, if WebMD wishes to make
    available to its Users certain Genetics and Genomics content in the
    Channels, and such content either are not available from KG or, in the
    reasonable opinion of WebMD, are not of acceptable quality, then WebMD may
    acquire and utilize such content from third parties; provided, however,
    WebMD will give KG notice of its request for additional content and KG will
    have twenty (20) days from the date of such notice to provide such content
    to WebMD (except in the event that such content are required in connection
    with a current news event which necessitates posting of relevant content
    within such 20 day period).

        2.8 WebMD agrees that, in the event it desires to provide to its Users
    one or more services related to Genetics and Genomics, such as, by the way
    of example, genetic counseling, storage of DNA samples, or referral
    services, it shall notify KG in writing, whereupon KG shall have the right,
    at its election, to exclusively negotiate with WebMD for a period of fifteen
    (15) days, the right to provide such service to WebMD for its Users, either
    by means of a link to the KG Site or by integrating such service on the
    WebMD Site.

3.  WEBMD SITE DEVELOPMENT; CO-BRANDED WEBMD SITES.

        3.1 The parties agree to integrate the KG Content into the Channels and
    to develop the Channels on a commercially reasonable basis in a
    collaborative manner as further agreed upon by the parties within sixty
    (60) days of the Effective Date. The parties intend that the Consumer
    Channel will be developed as soon as possible with a goal of [*], and that
    the Professional Channel will be developed as soon as possible with a goal
    of [*]. WebMD shall feature KG as a provider of Genetics and Genomics
    Content through the presentation of the KG Content (i) within the Channels,
    and (ii) on co-branded Web sites to be produced, developed, or participated
    in or contributed to by WebMD through agreements with certain WebMD portal
    partners, namely [*] (collectively, the "Portal Partners") as of the date
    hereof (and WebMD shall use commercially reasonable effort to feature KG as
    described in this Paragraph through WebMD's agreements with future Portal
    Partners (both present and future Portal Partner obligations being subject
    to the terms of those agreements between WebMD and such Portal Partner).
    WebMD shall have the exclusive right to sell and place advertising and
    sponsorships in connection with the Content, within the Channels, on the
    WebMD Site and on sites of the Portal Partners.

        3.2 In addition to the commitment made in Schedule 5 for a fixed
    advertising badge as part of the WebMD New Partner Launch Promotional
    Program for a period of [*] following Launch

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
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    (the "Launch Period"), WebMD will provide the following services
    (collectively, the "Services") to KG:

           (i) following the Launch Period, provide an advertising badge on a
       rotational basis on the WebMD Site home page for the equivalent of [*]
       for the entire Term of the Agreement;

           (ii) at such time as WebMD sells key word searches, provide
       references to the Channels in all key word searches on the WebMD for the
       words "Genetics" and "Genomics" (provided that during the term of the
       agreement, WebMD will not sell those search terms to any Competitive
       Genetics and Genomics Company in a manner that could be deemed directly
       competitive to the KG Business Purpose. WebMD represents that, as of the
       Effective Date, it does not sell key word searches, and nothing in this
       Agreement shall obligate WebMD to do so in the future;

           (iii) to the extent practicable and subject to the respective third
       party agreements, and only at such time as WebMD sells key word searches,
       provide references to the Channels in all key word searches on the Portal
       Partner sites for the words "Genetics" and "Genomics" (to the extent that
       such searches and key words are within WebMD's self-promotional inventory
       pursuant to its agreement with such Portal Partner), and to the extent
       those searches are not sold to other third parties;

           (iv) contextually integrate in appropriate channels in the WebMD
       Site, including but not limited to "Living Better" and "Condition
       Centers," action links to the Channels, subject to the editorial policies
       and practices of the WebMD Site;

           (v) to the extent practical and subject to the respective third party
       agreements, make reasonable commercial efforts to provide action links to
       the Channels, from related content areas and channels on the Portal
       Partner sites.

           (vi) subject to the advertising and editorial guidelines of WebMD,
       make reasonable commercial efforts to provide links to the Channels with
       other appropriate and relevant content areas of the WebMD site (as
       determined by WebMD in good faith), including but not limited to content
       within the "Medical Library" channel of the WebMD Site.

    The parties agree and acknowledge that, while initially these efforts will
be directed toward the Consumer Channel, they will, to the extent applicable,
subsequently also be directed to the Professional Channel, once the Professional
Channel is launched.

        3.3 Subject to the terms and conditions of this Agreement WebMD will
    create the Channels primarily for KG to provide the KG Content to Users.

        3.4 WebMD shall retain the sole editorial and artistic discretion with
    respect to the WebMD Site and the Channels and over the presentation
    including without limitation, the "look and feel" of the KG Content in the
    Channels and sole ownership of the Channel platform technology.

        3.5 WebMD agrees that no Competitive Genetics and Genomics Company will
    be permitted to post advertisements or other promotions on web pages within
    the WebMD Site for a purpose that is directly competitive with the KG
    Business Purpose; provided, however, WebMD may post advertisements of any
    third party with whom WebMD has a current contractual relationship as of the
    Effective Date and who has a contractual right to place such advertisements.

        3.6 KG will cooperate with WebMD to make available to WebMD, as
    reasonably requested, in a timely fashion any necessary resources of KG to
    integrate the KG Content or develop the Channels pursuant to the terms of
    this Agreement.

        3.7  COLLABORATION.  WebMD agrees to engage in good faith discussions
    with KG regarding collaboration in the development of the following Genetics
    and Genomics opportunities:

        (a) Developing, conducting and broadcasting live chats on the WebMD Site
    with Genetics and Genomics experts.

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        (b) Subject to execution of any necessary additional agreements,
    integrating the KG Content into community-based areas of the WebMD Site.

        (c) Meeting periodically (at least once per quarter) to discuss market
    opportunities and other areas of collaborative activity.

        (d) The parties agree to work together in good faith to define at what
    level a User will move from the WebMD Site to the KG Site for condition
    specific information and the gathering of specific phenotypic information,
    provided however, any links from the KG Content or the Channels to the KG
    Site or any other third party site shall be subject to the prior review and
    approval of WebMD. The parties agree that it is their intention that all
    users moving to the KG Site from the WebMD Site will be moved back to the
    WebMD Site.

        3.8  RELATIONSHIP MANAGERS.  The parties agree to each appoint a
    relationship manager (the "Relationship Manager"), whose roles shall include
    coordination of the parties' efforts under this Agreement to develop the
    Channels and integrate the KG Content and to serve as the primary point of
    contact for the other party.

4.  THIRD PARTY RELATIONSHIPS.

        4.1 To the extent permitted in its agreements with third party media
    companies with whom WebMD has current contractual relationships as of the
    Effective Date ("Media Partners"), WebMD shall, in its sole discretion, in
    good faith, and at its own cost, promote the Channels through a commercially
    reasonable amount of offline advertising (as determined by WebMD in good
    faith). Such advertising may include commercials to be run by, on behalf of,
    or for the benefit of WebMD on the commercial, cable and public television
    networks operated by the Media Partners or television program segments or
    spots (which, for example, may be 30, 45 or 60 seconds in duration) devoted
    to health issues that are run on such networks and that WebMD sponsors, or
    both (subject to the agreements with the respective Media Partner(s)).
    Production and run costs incurred in connection with the commercials,
    segments and spots described in this paragraph will be borne by WebMD. KG
    shall have reasonable approval of the storyboards for any such commercials,
    segments and spots using the KG name, which approval shall not be
    unreasonably withheld. For purposes of this provision, "promotion" shall
    mean expressly mentioning the name of the Channels or the availability of
    the KG Content in such advertising.

        4.2 In addition, WebMD will devote, in its sole discretion and in good
    faith, a commercially reasonable amount of its inventory of banner
    advertisement impressions available under its agreements with Portal
    Partners to promote the relationship between WebMD and KG.

5.  FEES AND REVENUE SHARING.

    In exchange for the performance of WebMD's obligations under this Agreement,
KG will pay WebMD those fees set forth on Schedule 5 attached hereto. In
addition, in exchange for delivery of and license to the KG Content, the parties
shall share revenue as set forth in Schedule 5.

6.  INTELLECTUAL PROPERTY MATTERS.

        6.1 OWNERSHIP OF KG CONTENT AND TECHNOLOGY. KG shall retain all right,
    title and interest in the KG Content provided by it to WebMD in connection
    with this Agreement, and all intellectual property rights related thereto.
    WebMD shall retain all right, title and interest in the technology provided
    by WebMD to KG in connection with this Agreement and all intellectual
    property rights related thereto.

        6.2  COLLECTION AND OWNERSHIP OF USER DATA.  WebMD shall own and shall
    not transfer or disclose to KG any personally identifiable information
    (collectively, the "WebMD User Information") collected, if any, from Users
    of the KG Content on the WebMD Site or within the Channels. KG shall own and
    shall not transfer or disclose to WebMD any personally identifiable and
    other information (collectively, the "KG User Information") collected from
    users of the KG

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    Site. The parties agree during the Term to continuously monitor and enhance
    their privacy policies and the management and use of information collected
    from or about end users to conform to industry standards and state and
    federal laws and regulations. Without limitation, the parties agree to erase
    all user signatures or other technical devices used to track movement
    between the WebMD Site and the KG Site. WebMD shall provide reports of
    aggregate information to KG on Channel metrics, all in a form and substance
    as provided by WebMD to other content providers within similar channels;
    such information shall not allow individuals to be identified or contacted
    by any means. KG may use the reports for KG's internal purposes only. WebMD
    shall have no obligation to collect any particular User information with
    respect to the KG Content or the Channels. All activities which a user could
    or should reasonably perceive as being provided by WebMD as part of the
    WebMD Site (even if it takes place as part of a co-branded activity or where
    the functionality is in fact provided by servers operated by KG) shall be
    exclusively subject to the then current terms and conditions of use and the
    privacy policy of WebMD. KG agrees and acknowledges that it obtains no
    ownership or other rights in and will refuse access to any personally
    identifiable information provided by Users of the WebMD Site.

        6.3  OWNERSHIP OF WEBMD SITE.  All right, title and interest in and to
    the WebMD Site and all elements thereof, including the Channels, any content
    (except the KG Content), graphics, trademarks (except KG trademarks), logos,
    and other materials of any type (in any form, format, forum, media, medium,
    means or method known or hereafter developed) appearing on or in the WebMD
    Site or the Channels, the look and feel thereof, and all technology related
    thereto are owned exclusively by WebMD and shall remain the property of
    WebMD. Nothing in this Agreement or in an attachment hereto creates in KG
    any rights in the WebMD Site or the Channels (as distinct from the KG
    Content). KG expressly agrees that all impressions and page views within the
    Channels and any pages of the WebMD Site that contain KG Content shall be
    allocated exclusively to WebMD for purposes of Media Metrix and any similar
    web viewership measuring service.

        6.4  TRADEMARK LICENSE.  KG hereby grants to WebMD a nonexclusive,
    nontransferable, worldwide, limited-scope license to use the trade names,
    trademarks and service marks (collectively, the "KG Trademarks") of KG in
    connection with this Agreement or in the promotion of the collaborative
    efforts undertaken or to be undertaken by WebMD. All use of the KG
    Trademarks shall inure to the benefit of KG. WebMD hereby grants to KG a
    nonexclusive, nontransferable, worldwide, limited-scope license to use the
    tradenames, trademarks and service mark of WebMD (collectively, the "WebMD
    Marks") in the promotion of the Channels or the KG Content, subject to the
    prior written approval of WebMD. All use of the WebMD Trademarks shall inure
    to the benefit of WebMD.

        6.5  PRIVACY POLICIES.  In addition to their obligations under
    Section 6.2, the parties agree that privacy and data protection laws and
    requirements are in a state of rapid change and agree to cooperate with one
    another in good faith in order to address such laws and requirements in a
    mutually agreeable manner, including the possible necessity of amending
    certain of the provisions and practices set forth in this Agreement. Each
    party agrees to use its of commercially reasonable efforts to ensure that,
    in the case of KG, the KG Content and all activities and content which KG
    contributes to the WebMD Site, and, in the case of WebMD, all activities and
    content on the Channels which WebMD contributes, are in compliance with all
    applicable laws and regulations and will remain in compliance throughout the
    Term hereof.

7.  WARRANTIES; INDEMNIFICATION; LIMITATION OF LIABILITY.

        7.1  REPRESENTATIONS, WARRANTIES AND COVENANTS.

        (a) KG represents, and warrants that (i) it shall not make any
    representations to any third party or take any actions inconsistent with the
    terms of this Agreement; (ii) the KG Content is or will be original to KG or
    KG has full and sufficient rights to grant to WebMD the rights and licenses
    granted hereunder; (iii) KG has used and shall use commercially reasonable
    efforts to

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    ensure the accuracy and integrity of the KG Content provided hereunder;
    (iv) neither the KG Content nor WebMD's use of the same in any manner
    contemplated hereunder shall infringe upon or violate the intellectual
    property rights, including without limitation copyright, trademark, trade
    secrets, patent rights, rights of publicity or personal rights, of any third
    party; and (vi) neither the execution of this Agreement nor KG's performance
    hereunder, will directly or indirectly violate or interfere with the terms
    of another agreement to which it is a party.

        (b) KG represents and warrants that, as of the Effective Date it is not,
    and covenants that during the Term it will not be, in the business of
    managing or conducting Clinical Trials on a contract basis. As used in this
    Section 7.1(b), "Clinical Trials" means a controlled study involving human
    subjects designed to evaluate prospectively the safety and effectiveness of
    new drugs or devices or of behavioral interventions.

        (c) WebMD represents and warrants that (i) it shall not make any
    representations to any third party or take any actions inconsistent with the
    terms of this Agreement; (ii) WebMD has full and sufficient rights to enter
    into this Agreement; (iii) WebMD has used and shall use commercially
    reasonable efforts to ensure the accuracy and integrity of the content and
    services provided in the WebMD Site; and (iv) no content contained in the
    WebMD site shall infringe upon or violate the intellectual property rights,
    including without limitation copyright, trademark, trade secrets, patent
    rights, rights of publicity or personal rights, of any third party (except
    that this statement shall not extend to KG Content, for which KG is
    responsible as set forth above).

        7.2  INDEMNITY OF WEBMD.  WebMD shall indemnify and hold harmless KG and
    its Affiliates agents, directors, officers, employees, and subcontractors
    for and from any and all liabilities, losses, obligations, risks, expenses
    (including reasonable attorneys' fees), costs, damages, and judgments, and
    against any and all claims and actions, brought by a third party and based
    upon or arising from (i) any material breach of the Agreement by WebMD,
    (ii) any material breach by WebMD of any material representation or warranty
    set forth in this Agreement, or (iii) WebMD's willful misconduct or gross
    negligence, or (iv) any material breach by WebMD of any agreement with any
    third party, including any Portal Partner, Media Partner or Quintiles
    Transnational Corporation (except to the extent such breach arises out of
    KG's breach of its covenants and obligations under this Agreement).

        7.3  INDEMNITY OF KG.  KG shall indemnify and hold harmless WebMD and
    its Affiliates, agents, directors, officers, employees, and subcontractors
    for and from any and all liabilities, losses, obligations, risks, expenses
    (including reasonable attorneys' fees), costs, damages, and judgments, and
    against any and all claims and actions, brought by a third party and based
    upon or arising from (i) any material breach of the Agreement by KG,
    (ii) any material breach by KG of any material representation or warranty
    set forth in this Agreement, (iii) the provision of the KG Content to WebMD
    for use in accordance with the terms hereof, or (iv) KG's willful misconduct
    or gross negligence.

        7.4  INDEMNIFICATION PROCEDURE.  If either party receives notice of an
    actual or threatened claim, cause, or action which may give rise to
    indemnification of it under this Agreement, that party (the "Indemnitee")
    shall promptly notify the other (the "Indemnitor") of the claim, cause or
    action; PROVIDED, HOWEVER, that failure to give such notice shall not
    relieve the Indemnitor of any liability hereunder (except to the extent the
    Indemnitor has suffered actual material prejudice by such failure). The
    Indemnitee shall tender sole defense and control of such claim to the
    Indemnitor; provided, however, Indemnitor is a named party to the claim. The
    Indemnitee shall, if requested by the Indemnitor, give reasonable assistance
    to the Indemnitor in defense of any claim. The Indemnitor shall reimburse
    the Indemnitee for any reasonable legal expenses directly incurred from
    providing such assistance, as such expenses are incurred. The Indemnitor
    shall have the right to consent to the entry of judgment with respect to, or
    otherwise settle, an indemnified claim with the prior written consent of the
    Indemnitee, which consent shall not be unreasonably withheld;
    provided, however, that the Indemnitee may withhold its consent if any such
    judgment or settlement imposes any unreimbursed monetary or continuing
    nonmonetary obligation on such

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    party or does not include an unconditional release of that party and its
    affiliates from all liability in respect of claims that are the subject
    matter of the indemnified claim.

        7.5  DISCLAIMER OF OTHER WARRANTIES.  EACH PARTY HEREBY ACKNOWELDGES AND
    AGREES THAT, EXCEPT AS EXPLICITLY PROVIDED FOR IN THIS AGREEMENT, THE OTHER
    PARTY MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, AS TO
    (A) THE USEFULNESS, ACCURACY, COMPLETENESS, FEASIBILITY, RELIABILITY OR
    EFFECTIVENESS OF SUCH PARTY'S SITES OR CONTENT; (B) THAT SUCH PARTY'S SITES
    OR CONTENT WILL OPERATE UNINTERRUPTED OR ERROR-FREE; OR (C) THAT DEFECTS IN
    SUCH PARTY'S SITES OR CONTENT HAVE BEEN OR WILL BE CORRECTED. WITHOUT
    LIMITING THE FOREGOING, EACH PARTY HEREBY DISCLAIMS ALL WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.

        7.6  EXCLUSION OF DAMAGES.  EXCEPT IN THE EVENT OF FRAUD OR WILLFUL
    MISREPRESENTATION OR MISCONDUCT, INDEMNITY CLAIMS PURSUANT TO SECTION 7, OR
    CLAIMS ARISING IN CONNECTION WITH SECTION 8, IN NO EVENT SHALL A PARTY TO
    THIS AGREEMENT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
    CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, FOR LOST PROFITS, IN
    ANY WAY ARISING OUT OF OR RELATING TO THIS AGREEMENT, EVEN IN THE EVENT SUCH
    PARTY HAS BEEN ADVISED AS TO THE POSSIBILITY OF SUCH DAMAGES.

8.  PROPRIETARY RIGHTS AND CONFIDENTIALITY.

        8.1  DEFINITIONS.

        (a) "CONFIDENTIAL INFORMATION" means any data, materials or information
    that is disclosed by either party to the other party during the term hereof,
    in oral or written form. Confidential Information also includes any
    information described in this section which either party obtains from
    another party under an obligation of confidentiality. Confidential
    Information does not include any data or information which the receiving
    party can demonstrate with competent written proof: (i) was already known to
    it at the time of disclosure; (ii) was independently developed by it without
    reference to the disclosing party's Confidential Information; (iii) is in
    the public domain; (iv) was rightfully disclosed to it by a third party
    without obligation of confidentiality; (v) is required to be disclosed
    pursuant to any statutory or regulatory authority or court order, provided
    the disclosing party is given prompt written notice of such requirement and
    the scope of such disclosure is limited to the extent possible.

        (b) "TRADE SECRETS" shall mean any Confidential Information of the party
    which owns and/or controls or has rights to such information, including but
    not limited to technical or non-technical data, a formula, a pattern, a
    compilation, a program, a device, a method, a technique, a drawing, a
    process, financial data, financial plans, product plans, or a list of actual
    or potential customers or suppliers, in any form or format, which is not
    commonly known by or available to the public and which: (i) derives economic
    value, actual or potential, from not being generally known to and not being
    readily ascertainable by proper means by other persons who can obtain
    economic value from its disclosure or use, and (ii) is the subject of
    efforts that are reasonable under the circumstances to maintain its secrecy.
    Trade Secrets specifically include any Confidential Information described
    herein that either party obtains from another party under an obligation of
    confidentiality.

        8.2  RESTRICTIONS.  During the Term, and indefinitely thereafter,
    neither party will, except as otherwise expressly directed by the other
    party, use, copy or disclose, or permit any unauthorized person access to,
    any of the other party's Trade Secrets, except as expressly permitted herein
    and necessary for accomplishment of activities required hereby. During the
    term of this Agreement and for a period of [*] after termination hereof,
    neither party will use, copy, or disclose, or permit any

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

    unauthorized person access to, any of the other party's Confidential
    Information, except as expressly directed by such party or as permitted
    herein.

        8.3  OWNERSHIP AND PROTECTION OF CONFIDENTIAL INFORMATION.  (a) Each
    party agrees that it has no interest in or right to use the Confidential
    Information of the other except in accordance with the terms of this
    Agreement. The party receiving Confidential Information shall (i) maintain
    it in strict confidence and take all reasonable steps to prevent its
    disclosure to third parties, except to the extent necessary to carry out the
    purposes of this Agreement, in which case these confidentiality restrictions
    shall be imposed upon the third parties to whom the disclosures are made;
    (ii) use at least the same degree of care as it uses in maintaining the
    secrecy of its own Confidential Information (but no less than a reasonable
    degree of care); and (iii) prevent the removal of any proprietary,
    confidential or copyright notices placed on the Confidential Information.

        (b) Each party consents to the filing of the Agreement with the U.S.
    Securities and Exchange Commission by the other party and to reference such
    party's name and a description of this Agreement in any such filings. In
    connection with any public disclosure or filing with any governmental
    agency, including the Securities and Exchange Commission, each party agrees
    to seek confidential treatment of the terms and conditions of this
    Agreement. In addition, any description of this Agreement, or any redacted
    version of this Agreement, intended to be filed or attached to any publicly
    filed document by a party shall be submitted to the other party for review
    and input prior to filing. Notwithstanding anything to the contrary herein,
    neither party may use any trademark of the other party in any public
    disclosure or filing with any governmental agency, including the Securities
    and Exchange Commission, without the express written consent of the other
    party, but this shall not be construed to restrict the use of a parties'
    corporate name by the other party in any such public disclosure or filing.

        8.4  REMEDIES FOR BREACH.  In the event of a breach of this Section 8,
    the parties agree that the non-breaching party may suffer irreparable harm
    and the total amount of monetary damages for any injury to the non-breaching
    party may be impossible to calculate and would therefore be an inadequate
    remedy. Accordingly, the parties agree that the non-breaching party may be
    entitled to temporary, preliminary and permanent injunctive relief against
    the breaching party, its officers or employees, in addition to such other
    rights and remedies to which it may be entitled at law or in equity.

        8.5  TERMS OF AGREEMENT; PUBLICITY.

        (a) The parties agree that the material terms of this Agreement will be
    considered the Confidential Information of each party. Notwithstanding the
    foregoing, each party shall have the right to disclose the material terms of
    this Agreement in confidence to any bona fide potential investor, investment
    banker, acquirer or merger partner, subject to the terms of a
    confidentiality agreement consistent with each of the terms hereof.

        (b) The parties agree that the public announcement of the execution of
    this Agreement shall be substantially in the form of a joint press release
    mutually agreed upon by the parties. Any other publication, news release or
    other public announcement relating to this Agreement or the performance
    hereunder shall first be reviewed and approved by both parties, which
    approval shall not be unreasonably withheld or delayed; except with respect
    to any disclosure which is required by law.

9.  TERMINATION; DISPUTE RESOLUTION.

        9.1 TERM. This Agreement shall commence on the Effective Date and shall
    continue in full force and effect for a period of five (5) years ("Initial
    Term") subject to the provisions hereof, unless earlier terminated as
    provided for below. This Agreement will automatically renew on a twelve
    (12) month basis unless terminated by either party in writing six
    (6) months prior to the end

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

    of the Initial Term or any renewal term (any such renewal term, together
    with the Initial Term, together referred to as "Term").

        9.2  EARLY TERMINATION.  Either party may terminate this Agreement
    immediately by notice to the other party upon the occurrence of any of the
    following events of default by the other party:

           (i) The other party fails to observe, perform or fulfill any of its
       material obligations, representations, or warranties (other than
       confidentiality obligations) under the Agreement and fails to cure such
       default as expeditiously as possible, but in no event later than sixty
       (60) days after the non-defaulting party gives written notice of such
       failure; provided, however, no cure period shall be applicable in the
       event the notifying party reasonably determines that the other party's
       performance or non-performance of its material obligations hereunder are
       in violation of any applicable law or regulation.

           (ii) The other party fails to observe, perform or fulfill any
       confidentiality obligation imposed hereunder and fails to cure such
       default within ten (10) days after the non-defaulting party gives notice
       of such failure; or

           (iii) The other party's business is liquidated, dissolved or
       suspended.

        9.3  REMOVAL OF KG CONTENT BY WEBMD.

        (a) WebMD may immediately remove the KG Content or portion(s) thereof,
    in whole or in part, in the event:

           (i) The KG Content either becomes or WebMD reasonably believes that
       such KG Content shall become the subject of a final judgment, agreement,
       or injunctive order that the KG Content infringes the ownership rights of
       any third party, that KG otherwise does not have the right to permit
       others to access such KG Content, or that the KG Content defames a third
       party or misappropriates any personal right of any third party; or

           (ii) WebMD reasonably believes that the KG Content is illegal or
       contrary to any acceptable law; or

           (iii) WebMD reasonably believes, or it is the opinion of any
       government regulatory authority, that the provision of such KG Content
       materially jeopardizes the health or safety of any person using or
       relying upon the KG Content; provided that, in such event WebMD shall
       promptly notify KG of its intention to so remove such KG Content.

        (b) In the event that the KG Content or any portion thereof is removed
    subject to this Paragraph 9.3, KG must, at its sole cost and expense, and at
    KG's option, either:

           (i) Procure for WebMD the right to continue using the KG Content; or

           (ii) Replace the KG Content, at its sole cost and expense, with
       substantially similar KG Content of either equivalent functionality and
       performance or value to the Channels.

        9.4  REMOVAL OF KG CONTENT.  (a) In the event KG reasonably believes
    that the KG Content:

           (i) will become the subject of a final judgment, agreement or
       injunctive order that the KG content infringes the ownership rights of
       any third party, that KG does not have the right to permit others to
       access such KG Content, or that the KG Content defames a third party or
       misappropriates any personal right of any third party;

           (ii) is illegal or contrary to any acceptable law; or

           (iii) materially jeopardizes the health or safety of any person, or
       is otherwise inaccurate or is not in compliance with applicable legal
       requirements, then KG shall thereupon immediately notify WebMD and WebMD
       shall thereupon immediately remove such KG Content or portions thereof.

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

        (b) In the event that KG content or any portion thereof is removed
    subject to this Paragraph 9.4, KG must, at its sole cost and expense, and at
    KG's option, either:

           (i) Procure for WebMD the right to continue using the KG Content; or

           (ii) Replace the KG Content, at its sole cost and expense, with
       substantially similar KG Content of equivalent functionality and
       performance or value to the Channels.

        9.5  SURVIVAL.  The provisions of the Agreement which by their nature
    are intended to survive termination or expiration of this Agreement shall
    survive expiration or termination of this Agreement.

        9.6  DISPUTE RESOLUTION.  In the event of a dispute between the parties
    and for which dispute the parties are unable to reach a mutually agreeable
    resolution, the dispute shall be submitted to binding arbitration under the
    commercial arbitration rules of the American Arbitration Association then in
    effect in Chicago, Illinois. There shall be one arbitrator mutually agreed
    to by both parties; such arbitrator shall have experience in the area of
    controversy. After the hearing, the arbitrator shall decide the controversy
    and render a written decision setting forth the issues adjudicated, the
    resolution thereof and the reasons for the award. The award of the
    arbitrator shall be conclusive. Payment of the expenses of arbitration,
    including the fee of the arbitrator, shall be assessed by the arbitrator
    based on the extent to which each party prevails. Notwithstanding the
    foregoing, any dispute related to the ownership of intellectual property,
    any violation of Section 8 hereof or any other action or proceeding required
    to maintain the status quo shall not be required to be submitted to
    arbitration as set forth above.

10. MISCELLANEOUS PROVISIONS.

        10.1  INDEPENDENT CONTRACTORS.  It is expressly agreed that WebMD and KG
    are acting under this Agreement as independent contractors, and the
    relationship established under this Agreement shall not be construed as a
    partnership, joint venture or other form of joint enterprise. Neither party
    is authorized to make any representations or create any obligation or
    liability, expressed or implied, on behalf of the other party, except as may
    be expressly provided for in this Agreement.

        10.2  ACCESS TO BOOKS AND RECORDS.  The parties shall keep complete,
    accurate and up-to-date books and records in accordance with generally
    accepted accounting principles and sound business practices covering all
    transactions relating to this Agreement. Either party or its authorized
    representatives (who shall be subject to the approval of the other party
    with such approval not to be unreasonably withheld), or both, shall at its
    expense, upon reasonable notice, and during normal business hours have the
    right (but not more than once annually) to inspect, audit, or copy such
    records in order to determine whether all provisions of this Agreement have
    been met. The parties agree that all information and records obtained in
    such audit shall be considered Confidential Information. This right to audit
    shall be available to either party for up to one (1) year following the
    termination of this Agreement.

        10.3  HEADINGS.  The headings of the sections and paragraphs of this
    Agreement are for convenience only and shall not be a part of or affect the
    meaning or interpretation of this Agreement.

        10.4  SCHEDULES.  This Agreement incorporates the attached Schedules and
    any subsequent Schedules to this Agreement.

        10.5  ASSIGNMENT.  This Agreement and any interest hereunder shall inure
    to the benefit of and be binding upon the parties and their respective
    successors, legal representatives and permitted assigns. Either party may
    assign this Agreement (i) to any legal entity in connection with the merger
    or consolidation of the assigning Party into such entity or the sale of all
    or substantially all of the assets of the assigning Party to such entity; or
    (ii) to any Affiliate of the assigning party. Except as stated in the
    previous sentence, neither party may assign or delegate this Agreement
    without the other party's prior written consent, which consent shall not be
    unreasonably withheld.

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

    Any attempt to assign, delegate or otherwise transfer the Agreement in
    violation of this Paragraph 10.5 is voidable by the other party by written
    notice delivered within three business days of such event giving rise to
    such right.

        10.6  NOTICES.  All notices and demands (collectively, "Notices")
    required or permitted by this Agreement shall be in writing and shall be
    effective upon receipt and shall be delivered by hand or mailed via
    commercially acceptable overnight courier or by registered or certified
    mail, return receipt required, first class postage prepaid, addressed as
    follows:

       If to KG:

       Kiva Genetics, Inc.
       2375 Garcia Avenue
       Mountain View, CA 94043
       Attn: Steven B. Lehrer, Chief Business Officer

       With a copy to:

       Cooley Godward LLP
       5 Palo Alto Square
       3000 El Camino Real
       Palo Alto, CA 94306
       Attn: Barbara A. Kosacz, Esq.

       If to WebMD:

       Healtheon/WebMD Corporation
       400 The Lenox Building
       3399 Peachtree Road, NE
       Atlanta, GA 30326
       Attn: General Counsel

       with a copy to:

       Alston & Bird LLP
       One Atlantic Center
       1201 W. Peachtree Street
       Atlanta, GA 30309-3424
       Attn: James A. Harvey, Esq.

    Either party may change the address or designated person for receiving
Notices by providing notice in accordance with this Paragraph 10.6.

        10.7  SEVERABILITY.  If any term of this Agreement is held as invalid or
    unenforceable, the remainder of this Agreement shall not be affected, and
    each term and provision shall be valid and enforced to the fullest extent
    permitted by law.

        10.8  ENTIRE AGREEMENT/AMENDMENTS.  Each party represents and warrants
    that it has the full right and authority to enter into this Agreement and to
    perform any and all obligations under this Agreement without violating the
    terms of any other agreement to which it is a party. This Agreement,
    including all schedules attached hereto, contains the entire agreement
    between the parties and supersedes all prior and contemporaneous proposals,
    discussions and writings by and between the parties and relating to the
    subject matter hereof. None of the terms of this Agreement shall be deemed
    to be waived by either party or amended or supplemented unless such waiver,
    amendment or supplement is written and signed by both parties. The
    invalidity or unenforceability of any particular provision of this
    Agreement, as determined by any court of competent jurisdiction or any
    appropriate legislature, shall not affect the other provisions hereof, and
    this Agreement shall be construed in all respects as if such invalid or
    unenforceable provision had been omitted.

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

        10.9  NO BROKER FEES.  Except as expressly provided herein, each party
    shall bear its owns costs incurred in performing under this Agreement.
    Without limiting the generality of the foregoing sentence, WebMD represents
    and warrants to KG, and KG represents and warrants to WebMD that no broker,
    finder, investment banker or other similar party is entitled to any
    brokerage, finder's or other fee or commission in connection with the
    transactions contemplated by this Agreement.

        10.10  GOVERNING LAW.  This Agreement shall be governed by and construed
    in accordance with the laws of the State of New York, without regard to its
    principals of conflict of law.

        10.11  COUNTERPARTS.  This Agreement may be executed in any number of
    counterparts, each of which when so executed and delivered shall be deemed
    an original, and such counterparts together shall constitute one and the
    same instrument. This Agreement may be signed and the signature pages faxed
    to the other party, with the originals to be forwarded by mail.

    IN WITNESS WHEREOF, WebMD and KG, intending to be legally bound by the terms
of this Agreement, have caused this Agreement to be executed by their duly
authorized representatives.

<TABLE>
<S>                                           <C>
KIVA GENETICS, INC.                           HEALTHEON/WEBMD CORPORATION

By:    /s/ Steven B. Lehrer                   By:    /s/ W. Michael Heekin
       ------------------------------------          ------------------------------------
Name:  Steven B. Lehrer                       Name:  W. Michael Heekin
       ------------------------------------          ------------------------------------
Title: Chief Business Officer                 Title: Executive Vice President
       ------------------------------------          ------------------------------------
Date:  March 16, 2000                         Date:  March 16, 2000
       ------------------------------------          ------------------------------------
</TABLE>

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

                                  SCHEDULE 1.2

                  COMPETITIVE GENETICS AND GENOMICS COMPANIES

    [*]




[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

SCHEDULE 5

ANNUAL FEE TO WEBMD

    KG shall pay to WebMD an annual fee for the services provided for herein as
follows (the "Annual Fee"): Contract Year 1--$3 million; Contract Year
2--$5 million; Contract Year 3--$5 million; Contract Year 4--$10 million; and
Contract Year 5--$10 million. In an effort to provide additional promotion for
the launch of the new Channels, KG will participate in the WebMD New Partner
Launch Promotional Program which provides, among other things, placement of a
fixed advertising badge located above the fold on the WebMD Site home page in a
size of approximately 140 X 60 pixels for no less than [*] (the "New Partner
Launch Promotional Program"). KG shall pay a fee to WebMD of $2 million for its
participation in such Program (the "New Partner Promotional Launch Program
Fee"). The Annual Fee (or, for Contract Year 1, the Annual Fee and the New
Partner Promotional Launch Fee) shall be paid as follows: In calendar-year [*],
with the first [*] payment (which shall be for the [*] of 2000) being due [*]
after the execution of this Agreement and with subsequent [*] payments being due
within [*] of the applicable [*].

REVENUE SHARING

    In addition, the parties shall share certain other revenues during the Term
hereof as follows:

ANNUAL PERCENTAGE PAYMENTS:

    During each year of the Term, WebMD agrees to pay KG [*] percent [*] of
WebMD Net Revenues, until such time as KG has received a [*] amount [*] that
year's Annual Fee (and, for Contract Year 1, the new Partner Launch Promotional
Program Fee), after which time WebMD agrees to pay KG the percentage share of
the WebMD Net Revenue as set forth in the following paragraph; provided that, if
the amount of WebMD Net Revenues in any year is [*] (and, for Contract Year 1,
[*]) for that year, WebMD will not be [*] KG with the [*] for that year, but
such [*] shall be [*] such that KG shall be entitled to [*] for the [*] until
such time as KG has [*] the amount [*] from the [*]. Moreover, if KG's portion
of WebMD Net Revenues in any [*] the Annual Fee for that year, the [*] shall be
[*] the amount [*] KG in subsequent [*]. WebMD shall not have any obligation to
[*] during the term hereof.

    During each year of the Term, after such time as KG has either [*] (and, for
Contract Year 1, [*]) and [*] pursuant to the preceding paragraph or received
such amount via a [*] that year and [*] from [*], KG shall be entitled to
receive the following percentages of revenue generated from advertising/
sponsorship and sales associated with the Channels and with the pages containing
KG Content within the WebMD Site and on the WebMD Sites of the Portal Partners,
as follows:

<TABLE>
<S>     <C>                                <C>
1.      Advertising/Sponsorship            [*]% of WebMD Net Advertising/
                                           Sponsorship Revenue

2.      e-Commerce goods and services      [*]% of WebMD Net Sales Revenue
        purchased on or                    through the Channels
</TABLE>

    WebMD shall be entitled to receive the remaining percentages of the
foregoing revenue not received by KG.

Definitions:

    "WEBMD NET REVENUES" shall mean the sum of WebMD Net Advertising/Sponsorship
Revenue and WebMD Net Sales Revenue.

    "WEBMD NET ADVERTISING/SPONSORSHIP REVENUE" shall mean the gross revenue
actually received by WebMD from advertising and sponsorship on the Channels and
the pages containing KG Content within the WebMD Site and on the WebMD Sites of
the Portal Partners less (i) WebMD's costs (including all direct third party
vendor costs), which shall be [*] of such [*] revenue, and (ii) revenue

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

sharing payable to Portal Partners and slotting and similar fees that are
incurred in connection with KG's e-commerce placement in the Portal Partners'
WebMD Site(s).

    "WEBMD NET SALES REVENUE" shall mean the gross revenue actually received by
WebMD in connection with the sale of any product or service on the Channels or
the pages containing KG Content within the WebMD Site or on the Portal Partners'
(as the case may be) excluding shipping and handling charges (and excluding any
value added tax) less (a) returns, (b) deductions made for any cash, trade or
other discounts offered by the selling party at any time, (c) bad debts,
(d) the selling party's direct costs for advertising, sales, product costs,
distribution and other reasonable and appropriate costs, and (e) revenue sharing
due and payable to Portal Partners and slotting and similar fees that are
incurred in connection with KG's e-commerce placement in the Portal partner's
WebMD Site(s).

    Notwithstanding the foregoing, the parties agree that, at the end of [*],
the parties shall meet and confer in good faith to review the parties' progress
in meeting their objectives under this Agreement and how every party intends to
meet their objectives on a going forward basis.

                                FIRST AMENDMENT

    THIS FIRST AMENDMENT is made as of this 5th day of January, 2001, by and
between DNA SCIENCES, INC., a Delaware corporation formerly known as Kiva
Genetics, Inc., having its principal place of business at 6540 Kaiser Drive,
Fremont, CA 94555 ("DNAS") and WEBMD CORPORATION formerly known as
HEALTHEON/WEBMD CORPORATION, a Delaware corporation, having its principal place
of business at 400 The Lenox Building, 3399 Peachtree Road NE, Atlanta, Georgia
30327 ("WebMD").

                                    RECITALS

    A. The parties previously entered into a Collaboration Agreement, dated
March 16, 2000 (the "Agreement") and now desire to amend the Agreement as set
forth herein.

    B.  All terms defined in the Agreement shall, unless the context otherwise
requires, have the same meaning in this Amendment. Any reference in the
Agreement to Kiva Genetics or KG hereby applies to DNAS as one in the same
party.

                                  WITNESSETH:

    NOW THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth, the parties agree to add the following provisions to the
Agreement as follows:

1.  WEBMD CONTENT

    During the term of the Agreement, WebMD shall make available to DNAS for
placement on the KG Site the full text of certain content owned by WebMD,
including but not limited to articles, features, and online guest chat
transcripts all selected by WebMD, in its sole discretion (collectively the
"WebMD Content"). In making the selection of the WebMD Content, WebMD will
consider requests for particular items of content made by DNAS, but after such
consideration, WebMD, in its sole discretion, shall select the content to be
included in the WebMD Content. WebMD shall place the WebMD Content on a secure
web server for DNAS to download and place on KG Site, and the WebMD Content will
not be used in any other manner by DNAS.

    At WebMD's request, for any reason, DNAS shall remove all or any portion of
the WebMD Content from the KG Site within three (3) business days.

    Each page of the KG Site that displays any of the WebMD Content shall
prominently display the WebMD name, logo and copyright notice, as approved by
WebMD in advance. Each appearance of the WebMD name or logo will contain a
hyperlink to such page of the WebMD Site as specified by WebMD. For purposes of
this Amendment, the WebMD name and logo shall be considered part of the "WebMD
Content."

[*] CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

<PAGE>

2.  LICENSE TO WEBMD CONTENT

    WebMD hereby grants DNAS a limited, fully paid, non-exclusive, royalty-free,
license to use, reproduce, publish, perform and display the WebMD Content on a
single web site of DNAS in the United States intended for use by residents of
the United States, but only to the extent that such WebMD Content is owned by
WebMD or its licensed to WebMD with the right to sublicense without the payment
of any additional compensation. WebMD acknowledges that the WebMD Content
appearing on such site of DNAS may be viewed by persons located outside of the
United States, which shall not be considered a violation of this Agreement so
long as DNAS does not store or serve such WebMD Content on or from any servers
located outside of the United States. Any other use or display of the WebMD
Content by DNAS shall require the prior written consent of WebMD. DNAS may not
edit, alter the form of format of any WebMD Content without the prior written
approval of WebMD.

3.  TERM OF AGREEMENT

    The first sentence in Section 9.1 of the Agreement is hereby deleted in its
entirety and replaced with the following: "This Agreement shall commence on the
Effective Date and shall continue in full force and effect for a period of five
(5) years and three (3) months ("Initial Term") subject to the provisions
hereof, unless earlier terminated as provided for below." The additional three
(3) month period does not effect the Annual Fee Payment schedule set forth in
Schedule 5 of the Agreement.

4.  ENTIRE AGREEMENT AND AMENDMENT

    The Agreement and this Amendment, are the entire understanding and agreement
of the parties, and supersedes any and all oral or written agreements or
understandings between the parties, as to the subject matter of herein. Except
as expressly set forth herein, the Agreement and this Amendment may be changed
only by a writing signed by both parties.

5.  COUNTERPARTS

    This Amendment may be executed in one or more counterparts, each of which
shall be deemed on original and all of which shall be taken together and deemed
to be one instrument. A facsimile signature shall be deemed an original for
purposes of this Amendment.

    IN WITNESS WHEREOF, this Amendment #1 is executed in duplicate as of the
date and year first above written.

<TABLE>
<S>                                            <C>
HEALTHEON/WEBMD, INC.                          DNA SCIENCES, INC.

By:          /s/ K. Robert Draughan            By:          /s/ Steven B. Lehrer
             -------------------------------                -------------------------------
Print Name:  K. Robert Draughan                Print Name:  Steven B. Lehrer
             -------------------------------                -------------------------------
Title:       Executive Vice President          Title:       Chief Business Officer
             -------------------------------                -------------------------------
</TABLE>

[*] = Certain confidential information contained in this document, marked by
brackets, has been omitted and filed separately with the Securities and Exchange
Commission pursuant to Rule 406 of the Securities Act of 1933, as amended.