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                                                                   EXHIBIT 10.33


                             HYSEQ, INC. LETTERHEAD


                                November __, 2002

[EXECUTIVE NAME]
[ADDRESS]

               Re:    Severance Agreement

Dear Mr/s. _______________:

               Hyseq, Inc. (the "Company"), Vertical Merger Corp. ("Merger Sub")
and Variagenics, Inc. ("Variagenics") are parties to that certain Agreement and
Plan of Merger (the "Merger Agreement"), pursuant to which Merger Sub will merge
with and into Variagenics and Variagenics shall become a wholly owned subsidiary
of the Company (the "Merger").

               The Company considers it essential to the best interests of its
shareholders to foster the continuous employment of the Company's key management
personnel. In this regard, the Company's Board of Directors (the "Board")
recognizes that the uncertainty and questions raised by the Merger could result
in the departure or distraction of management personnel to the detriment of the
Company and its shareholders.

               The Board has decided to reinforce and encourage the continued
attention and dedication of members of the Company's management, including
yourself, to their assigned duties without the distraction arising from the
Merger.

               In order to induce you to remain in its employ, the Company
desires that you receive certain severance benefits in the event your employment
with the Company your employment is terminated within the 6-month period
immediately following the closing of the Merger pursuant to the Merger Agreement
(the "Closing") (i) by the Company other than for Cause or (ii) by you for Good
Reason (as defined below) (a termination of your employment under the
circumstances described in this sentence is sometimes hereinafter referred to as
a "Payment Termination"). This letter agreement (this "Agreement") confirms the
terms of those severance benefits.

               1. Termination Following Closing.

               (a) In the event that your employment with the Company is
terminated as a result of a Payment Termination, then, in addition to any
severance benefits to which you may otherwise be entitled under any severance
plan or program of the Company, (x) the Company shall pay to you your full
earned but unpaid base salary, when due, through the date of termination at the
rate in effect at the time notice of termination is given, plus all other
amounts to which you are entitled under any compensation plan or practice of the
Company at the time such payments are due, (y) you shall be entitled to receive
6 months of salary continuation of your base salary as in effect at the time
notice of termination is given, payable over the 6-month period commencing on
the date of termination at the same intervals as your base salary was paid
immediately prior to termination of employment, and (z) for the period beginning
on the date of termination and ending on the date which is 6 months following
the date of termination, the Company shall pay for and provide you and your
dependents with the same benefits coverage to


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which you would have been entitled had you remained continuously employed by the
Company during such period. At the termination of the benefits coverage under
clause (z) above, you and your dependents shall be entitled to continuation
coverage pursuant to Section 4980B of the Internal Revenue Code of 1986, as
amended (the "Code"), Sections 601-608 of the Employee Retirement Income
Security Act of 1974, as amended, and under any other applicable law, to the
extent required by such laws, as if you had terminated employment with the
Company on the date such benefits coverage terminates. You shall not be required
to mitigate the amount of any payment provided for in this Section 1(a) by
seeking other employment or otherwise, nor shall the amount of any payment
provided for in this Section 1(a) be reduced by any compensation earned by you
as the result of employment by another employer or self-employment, by
retirement benefits, by offset against any amounts (other than loans or advances
to you by the Company) claimed to be owed by you to the Company, or otherwise.

               (b) In the event that your employment with the Company is
terminated for any reason other than a Payment Termination, the Company shall
pay you your full earned but unpaid base salary, when due, through the date of
termination at the rate in effect at the time notice of termination is given or
your date of termination, in the event of termination as a result of your death,
plus all other amounts to which you are entitled under any compensation plan or
practice of the Company at the time such payments are due, and the Company shall
have no further obligations to you under this Agreement.

               (c) The Company may terminate your employment for Cause. For
purposes of this Agreement, "Cause" shall mean (i) gross negligence or willful
misconduct in the performance of duties to the Company where such gross
negligence or willful misconduct has resulted or is likely to result in
substantial and material damage to the Company or its subsidiaries; (ii)
repeated unexplained or unjustified absence from the Company; (iii) a material
and willful violation of any federal or state law; (iv) commission of any act of
fraud with respect to the Company; or (v) conviction of a felony or a crime
involving moral turpitude causing material harm to the standing and reputation
of the Company, in each case as determined in good faith by the Board.

               (d) You may terminate your employment with the Company for Good
Reason. For purposes of this Agreement, "Good Reason" shall mean the occurrence,
after the Closing, of any one or more of the following events without your prior
written consent, unless the Company fully corrects the circumstances
constituting Good Reason (provided such circumstances are capable of correction)
prior to the date of termination:

                      (i) any change in your position with the Company that
materially reduces your duties or level of responsibility as in effect
immediately preceding the Closing;

                      (ii) any reduction of your base compensation (other than
in connection with a general decrease in base salaries for most similarly
situated employees of the Company or a successor corporation); or

                      (iii) the relocation of the Company's offices at which you
are principally employed immediately prior to the date of the Closing to a
location more than 30 miles from such offices.

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        Your continued employment shall not constitute consent to, or a waiver
of rights with respect to, any circumstance constituting Good Reason hereunder.

               2. Successors; Binding Agreement. This Agreement shall inure to
the benefit of and be enforceable by you and your personal or legal
representatives, executors, administrators, successors, heirs, distributees,
devisees and legatees. If you should die while any amount would still be payable
to you hereunder had you continued to live, all such amounts, unless otherwise
provided herein, shall be paid in accordance with the terms of this Agreement to
your devisee, legatee or other designee or, if there is no such designee, to
your estate.

               3. Notice. For purposes of this Agreement, notices and all other
communications provided for in this Agreement shall be in writing and shall be
deemed to have been duly given when delivered or mailed by United States
certified or registered mail, return receipt requested, postage prepaid,
addressed to the respective addresses set forth on the first page of this
Agreement, provided that all notices to the Company shall be directed to the
attention of its General Counsel, or to such other address as either party may
have furnished to the other in writing in accordance herewith, except that
notice of change of address shall be effective only upon receipt.

               4. Miscellaneous. No provision of this Agreement may be modified,
waived or discharged unless such waiver, modification or discharge is agreed to
in writing and signed by you and such officer as may be specifically designated
by the Board. No waiver by either party hereto at any time of any breach by the
other party hereto of or compliance with, any condition or provision of this
Agreement to be performed by such other party shall be deemed a waiver of
similar or dissimilar provisions or conditions at the same or at any prior or
subsequent time. No agreements or representations, oral or otherwise, express or
implied, with respect to the subject matter hereof have been made by either
party which are not expressly set forth in this Agreement. The validity,
interpretation, construction and performance of this Agreement shall be governed
by the laws of the State of California without regard to its conflicts of law
principles. Any payments provided for hereunder shall be paid net of any
applicable withholding required under federal, state or local law. The section
headings contained in this Agreement are for convenience only, and shall not
affect the interpretation of this Agreement.

               5. Severability. The invalidity or unenforceability of any
provision of this Agreement shall not affect the validity or enforceability of
any other provision of this Agreement, which shall remain in full force and
effect.

               6. Counterparts. This Agreement may be executed in several
counterparts, each of which shall be deemed to be an original but all of which
together shall constitute one and the same instrument.

               7. Entire Agreement. This Agreement sets forth the entire
agreement of the parties hereto in respect of the subject matter contained
herein and supersedes all prior agreements, promises, covenants, arrangements,
communications, representations or warranties, whether oral or written, by any
officer, employee or representative of any party hereto. Any of your rights
hereunder shall be in addition to any rights you may otherwise have under
benefit plans or agreements of the Company to which you are a party or in which
you are a participant, including, but not limited to, any Company sponsored
employee benefit plans and stock options

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plans. The provisions of this Agreement shall not in any way abrogate your
rights under such other plans and agreements.

               8. At-Will Employment. Nothing contained in this Agreement shall
(a) confer upon you any right to continue in the employ of the Company, (b)
constitute any contract or agreement of employment, or (c) interfere in any way
with the at-will nature of your employment with the Company.

               If this letter sets forth our agreement on the subject matter
hereof, kindly sign and return to the Company the enclosed copy of this letter,
which shall then constitute our agreement on this subject.


                                       Sincerely,


                                       HYSEQ, INC.



                                       By:
                                           -------------------------------------

                                       Name:
                                       Its:



Agreed and Accepted,
this ______ day of November, 2002.




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[EXECUTIVE NAME]