EXHIBIT 10.22.2


                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                           UNDER 17 C.F.R. SECTIONS 200.80(B)(4)
                                                                   AND 240.24B-2


                   FIRST AMENDMENT TO JOINT VENTURE AGREEMENT

between

Lynx Therapeutics Inc., 25861 Industrial Boulevard, Hayward, California, 94545,
USA (hereinafter referred to as "LYNX")

and

BASF Aktiengesellschaft, 67056 Ludwigshafen, Germany
(hereinafter referred to as "BASF")


WHEREAS LYNX and BASF are parties to that certain Joint Venture Agreement dated
June 28/29, 2001 (the "Agreement"), pursuant to which LYNX and BASF agreed to
prepare the Joint Venture Company ("JVC") for and to initiate and complete an
IPO,

WHEREAS, BASF and LYNX have agreed in Art. 5 of the Agreement to increase the
share capital of the JVC in the next general shareholders' meeting;

WHEREAS, BASF and LYNX intend to hold the next general shareholders' meeting
between August 29 and 31, 2001 and are interested in amending the terms of the
Agreement with respect to the manner in which the increase of the share capital
shall be conducted;

NOW, THEREFORE, BASF and LYNX hereby agree that the terms of the Agreement are
amended as follows:

1)    Art. 5.1 of the Agreement is deleted and replaced in its entirety with the
      following:

      "The share capital of the JVC shall be increased from [...***...] to
      [...***...] by converting other reserves ("Andere Gewinnrucklagen") of the
      JVC and further by [...***...] to [...***...], the shares shall be
      converted into ordinary bearer shares with a nominal value of [...***...]
      each. BASF shall procure that BASF Holding, and Lynx shall procure that
      Lynx Holding shall vote for the respective proposal and change of the
      Articles of Association of the JVC at the next general meeting of JVC's
      shareholders."

2)    Art. 5.2 of the Agreement is deleted and replaced in its entirety with
      the following:

      "BASF shall procure that BASF Holding and LYNX shall procure that LYNX
      Holding respectively shall subscribe for shares according to their current
      shareholding in the JVC. The right of all other shareholders to subscribe
      for new shares shall be excluded. BASF shall procure that BASF Holding
      pays [...***...] and Lynx shall procure that Lynx

***   CONFIDENTIAL TREATMENT REQUESTED

                                      -2-


      Holding pays [...***...] to the JVC by [...***...] with regard to the
      increased capital subscribed by them.

      BASF shall procure that BASF Holding and LYNX shall procure that LYNX
      Holding respectively transfer - pro rata according to their current
      shareholdings in the JVC - shares up to a total of [...***...] percent of
      JVC's aggregate share capital to the JVC's employees, members of its
      Executive Board and Scientific Advisory Board and certain other
      collaborators. The shares shall be transferred as directed by the JVC at a
      price of [...***...] which shall be debited to the JVC by BASF
      Holding and LYNX Holding respectively. The payment for such shares shall
      be deferred and the JVC's respective liability shall only be extinguished
      by the merger of BASF Holding and LYNX Holding as creditors and the JVC as
      debtor."

2)    Art. 5.3 of the Agreement is deleted in its entirety.

3)    Art. 5.4 of the Agreement shall be deleted and replaced in its entirety by
      the following:

      "The JVC's employees, members of its Executive Board and Scientific
      Advisory Board and certain other collaborators shall receive their shares
      resulting from the capital increase [...***...]. The JVC shall bear the
      income tax owed by the recipients attributable to the granting of the
      shares subject to certain prerequisites (e.g. taking into account past and
      future service with/for the JVC) to be decided by the JVC."


                                           
Hayward, California, this 7th August 2001     Ludwigshafen, this 14th August 2001
Lynx Therapeutics, Inc.                       BASF Aktiengesellschaft


/s/ Norman Russell                            /s/ ppa Joachim Scholz  /s/ ppa Monde
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*** CONFIDENTIAL TREATMENT REQUESTED