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                                                                   EXHIBIT 10.13

                                   HYSEQ, INC.
                      SCIENTIFIC ADVISORY BOARD/CONSULTANTS
                                STOCK OPTION PLAN


                                   1. GENERAL

1.1   PURPOSE:

      Hyseq Inc., a Nevada corporation (the "Company"), hereby adopts this
Scientific Advisory Board/Consultants Stock Option Plan. This plan shall be
known as the HYSEQ, INC. SCIENTIFIC ADVISORY BOARD/CONSULTANTS STOCK OPTION PLAN
(the "Plan"). The purpose of the Plan is to foster and promote the long-term
financial success of the Company and materially increase stockholder value by:
(a) motivating superior performance by means of long-term performance related
incentives, (b) encouraging, and providing a means to obtain, an ownership
interest in the Company, (c) attracting and retaining outstanding talent by
providing incentive compensation opportunities competitive with other companies
and (d) enabling certain key non-employees to participate in the long-term
growth and financial success of the Company.

1.2   ADMINISTRATION:

      (a)   The Plan shall be administered by the Compensation Committee of the
Board of Directors of the Company (the "Board") or such other committee of
directors as is designated by the Board (the "Committee"), which shall consist
of two or more members. The members shall be appointed by the Board, and any
vacancy on the Committee shall be filled by the Board.

      (b)   Subject to the limitations of the Plan, the Committee shall have the
sole and complete authority: (i) to interpret the Plan and to adopt, amend and
rescind administrative guidelines and other rules and regulations relating to
the Plan, (ii) to correct any defect or omission or to reconcile any
inconsistency in the Plan or in any award granted hereunder and (iii) to make
all other determinations and to take all other actions necessary or advisable
for the implementation and administration of the Plan. The Committee's
determinations on matters within its authority shall be conclusive and binding
upon the Company and all other persons.

      (c)   All expenses associated with the Plan shall be borne by the Company.

      (d)   The Committee may, to the extent that any such action will not
prevent the Plan from complying with Rule 16b-3, delegate any of its authority
hereunder to such persons as it deems appropriate.






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1.3   PARTICIPATION:

      Participation in the Plan shall be limited only to those individuals
who are non-employee members of the Scientific Advisory Board (the "SAB") of the
Company (each an "SAB Member") or other non-employee consultants of the Company
who are designated by the Board or the Committee as being eligible to be granted
one or more Options under the Plan (a "Participant") . Notwithstanding the
foregoing, Options shall only be granted to consultants under the Plan if (i)
the consultant is a natural person and the consultant provides bona fide
services to the Company which services are not in connection with the offer or
sale of securities in a capital raising transaction, and do not directly or
indirectly promote or maintain a market for the Company's securities, or (ii) if
registration of the shares of Common Stock subject to such options is otherwise
permitted under the Securities Act of 1933 on a Form S-8.

1.4   TYPES OF AWARDS UNDER PLAN:

      Awards under the Plan will be in the form of non-statutory stock options
("Options"), as described in Article 2.

1.5   SHARES SUBJECT TO THE PLAN:

      Shares of stock covered by Options granted under the Plan may be, in
whole or in part, authorized and unissued or treasury shares of the Company's
common stock, $.001 par value per share, or such other shares as may be
substituted pursuant to Section 3.2 ("Common Stock"). The maximum number of
shares of Common Stock which may be issued for all purposes under the Plan shall
be thirty thousand (30,000) (subject to adjustment pursuant to Section 3.2). Any
shares of Common Stock subject to an Option which, for any reason, is canceled
or terminated without having been exercised, shall again be available for
Options under the Plan. No fractional shares shall be issued, and the Committee
shall determine the manner in which fractional share value shall be treated.

1.6   GENDER AND NUMBER:

      Except when otherwise indicated by the context, words in the masculine
gender when used in the Plan shall include the feminine gender, the singular
shall include the plural, and the plural shall include the singular.





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                                2. STOCK OPTIONS

2.1   AWARD OF STOCK OPTIONS:

      (a)  On the later of the (i) the first meeting of the SAB Members
following the effective date of the Plan or (ii) date on which an individual
first becomes an SAB Member, such SAB Member will automatically be awarded a
stock Option (an "Initial Option" or the "Initial Options") under the Plan to
purchase 1,000 shares of Common Stock (subject to adjustment pursuant to Section
3.2). Thereafter, effective on the date of each annual meeting (the "Annual
Meeting") of the stockholders of the Company (the "Stockholders"), commencing
with the Annual Meeting of the Stockholders held in 2001, each SAB Member then
in office who satisfies the conditions set forth in Section 1.3, shall
automatically be awarded an additional stock Option (a "Subsequent Option" or
the "Subsequent Options") to purchase 1,750 shares of Common Stock.

      (b)  In addition to the Initial Option and the Subsequent Option grants
to SAB Members as set forth in Section 2.1a, the Committee may at anytime and
from time to time grant one or more Options to one or more Participants who
satisfies the conditions set forth in Section 1.3, and may designate the number
of shares to be subject to each Option so granted, and the vesting schedule
thereof as provided in Section 2.4(d).

2.2   STOCK OPTION AGREEMENTS:

      The award of an Option shall be evidenced by a signed written agreement
(a "Stock Option Agreement") containing such terms and conditions as the
Committee may from time to time determine.

2.3   OPTION PRICE:

      The purchase price of Common Stock under each Option (the "Option
Price") shall be not less than the Fair Market Value of the Common Stock on the
date the Option is awarded.

2.4   EXERCISE AND TERM OF OPTIONS:

      (a)  Options may be exercised, in whole or in part, by the delivery of
written notice of exercise and payment of the aggregate Option Price for the
shares to be purchased to the Corporate Secretary of the Company. On the date
specified in such written notice, the Company shall accept payment for the
Option shares in cash, by bank or certified check, by wire transfer, or by such
other means as may be approved by the Committee. If approved in advance by the
Committee, payment may also be made (i) by delivering shares of Common Stock
already owned for at least six (6) months by the Participant and which have a
total Fair Market Value on the date of such delivery equal to the Option Price;
(ii) by authorizing the Company to retain Option




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shares that otherwise would be issuable upon exercise of the Option having a
total Fair Market Value on the date of delivery equal to the Option Price; (iii)
by the delivery of cash or the extension of credit by a broker-dealer to whom
the Participant has submitted a notice of exercise or otherwise indicated an
intent to exercise an Option (in accordance with part 220, Chapter II, Title 12
of the Code of Federal Regulations, a so-called "cashless" exercise); or (iv) by
any combination of the foregoing. As soon as practicable after receipt of each
notice and full payment, the Company shall deliver to the Participant a
certificate or certificates representing the acquired shares of Common Stock.

      (b)  Each certificate for shares issued upon exercise of an Option, unless
at the time of exercise such shares are registered with the Securities and
Exchange Commission (the "Commission"), under the Securities Act of 1933, as
amended (the "Act"), shall bear the following legend:

      NO SALE, TRANSFER, PLEDGE OR OTHER DISPOSITION OF THESE SHARES SHALL BE
      MADE EXCEPT PURSUANT TO REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS
      AMENDED, OR PURSUANT TO AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY
      THAT REGISTRATION IS NOT REQUIRED.

      Any certificate issued at any time in exchange or substitution for any
certificate bearing such legend (except a new certificate issued upon completion
of a public distribution pursuant to a registration statement under the Act of
the securities represented thereby) shall also bear the above legend unless, in
the opinion of such counsel as shall be reasonably approved by the Company, the
securities represented thereby need no longer be subject to such restrictions.

      (c) The Initial Option shall become exercisable on the date of grant. The
Initial Option shall continue to be exercisable until the first to occur of the
tenth anniversary of the date of grant or thirty (30) days following the date
the Participant ceases to be a member of the SAB. Each of an SAB Member's
Subsequent Options shall become exercisable on the date of grant (the date of
each Annual Meeting) and shall continue to be exercisable until the first to
occur of the tenth anniversary of the date on which the Subsequent Option(s) was
granted or thirty (30) days following the date the Participant ceases to be an
SAB Member. Notwithstanding the foregoing, in the event that a Participant
ceases to be an SAB Member as the result of his termination for "cause" (as
defined herein), all of the Participant's outstanding Options shall immediately
terminate.

      (d) All Option grants other than the Initial Options and the Subsequent
Options shall become exercisable upon the date or dates prescribed by the
Committee, and the Committee may provide that such Option rights become
exercisable in installments over a period of years, or upon the attainment of
stated goals; provided, however, no Option granted hereunder shall be
exercisable beyond the tenth anniversary of the date the Option is granted. A
Participant who




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ceases to be engaged as a consultant by the Company for any reason other than
for cause, may exercise any Option granted to such Participant, to the extent
that the right to purchase shares thereunder has become exercisable on the date
the Participant's services are terminated, but only within thirty (30) days
after the date the Participant's services are terminated, or, if earlier, within
the originally prescribed term of the Option, and subject to the condition that
no Option shall be exercisable after the expiration of the term of the Option.
Notwithstanding the foregoing, in the event that a Participant's services are
terminated by the Company for cause, all of the Participant's outstanding
Options shall immediately terminate.


                          3. MISCELLANEOUS PROVISIONS

3.1   NON-TRANSFERABILITY:

      No Option under the Plan, and no interest therein, shall be transferable
by the Participant otherwise than by will or, if the Participant dies intestate,
by the laws of descent and distribution. All Options shall be exercisable or
received during the Participant's lifetime only by the Participant or his legal
representative. Any transfer contrary to this Section 3.1 will nullify the
Option.

3.2   ADJUSTMENTS UPON CERTAIN CHANGES:

      (a) If the outstanding shares of Common Stock are increased, decreased or
changed into, or exchanged for, a different number or kind of shares or
securities of the Company through a reorganization or merger in which the
Company is the surviving entity, or through a combination, recapitalization,
reclassification, stock split, stock dividend, stock consolidation or otherwise,
an appropriate adjustment shall be made in the number and kind of shares that
may be issued pursuant to Options. A corresponding adjustment to the
consideration payable with respect to Options granted prior to any such change
shall also be made. Any such adjustment, however, shall be made without change
in the total payment, if any, applicable to the portion of the Option not
exercised but with a corresponding adjustment in the price for each share.

      (b) Upon the dissolution or liquidation of the Company, or upon a
reorganization, merger or consolidation of the Company with one or more
corporations as a result of which the Company is not the surviving corporation
or upon sale of all or substantially all of the Company's property, the Plan
shall terminate, and any outstanding Options shall terminate and be forfeited.
Notwithstanding the foregoing, the Committee may provide in writing in
connection with, or in contemplation of, any such transaction for any or all of
the following alternatives (separately or in combinations): (i) for the
assumption by the successor corporation of the Options theretofore granted or
the substitution by such corporation for such Options of options covering the
stock of the successor corporation, or a parent or subsidiary thereof, with
appropriate adjustments as to the number and kind of shares and prices; (ii) for
the continuance







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of the Plan by such successor corporation in which event the Plan and the
Options shall continue in the manner and under the terms so provided; or (iii)
for the payment in cash or shares of Common Stock in lieu of and in complete
satisfaction of such Options.

3.3   TAX WITHHOLDING:

      (a)   The Company shall have the power to withhold, or require a
Participant to remit to the Company, an amount sufficient to satisfy any
withholding or other tax due from the Company with respect to any amount payable
and/or shares issuable under the Plan, and the Company may defer such payment or
issuance unless indemnified to its satisfaction.

      (b)   Subject to the consent of the Committee, due to the exercise of an
Option, a Participant may make an irrevocable election (an "Election") to (A)
have shares of Common Stock otherwise issuable upon such exercise withheld, or
(B) tender back to the Company shares of Common Stock received pursuant to such
exercise or (C) deliver back to the Company pursuant to such exercise previously
acquired shares of Common Stock of the Company having a Fair Market Value
sufficient to satisfy all or part of the Participant's estimated tax obligations
associated with the transaction. Such Election must be made by an SAB Member
prior to the date on which the relevant tax obligation arises (the "Tax Date").
The Committee may disapprove of any Election, may suspend or terminate the right
to make Elections, or may provide with respect to any Option under this Plan
that the right to make Elections shall not apply to such Options.

3.4   CONDITIONS ON OPTIONS:

      In addition to the other terms hereof, in the event a Participant's
status as an SAB Member ceases by reason of disability while holding any Option,
the rights of such Participant to any such Option shall be subject to the
conditions that until any such Option is exercised, he shall (a) not engage,
either directly or indirectly, in any manner or capacity as advisor, principal,
agent, partner, officer, director, employee, member of any association or
otherwise, in any business or activity which is at the time competitive with any
business or activity conducted by the Company and (b) be available at reasonable
times for consultations (which shall not require substantial time or effort) at
the request of the Company's management with respect to phases of the business
with which he was actively connected, but such consultations shall not be
required to be performed at any place or places outside of the United States of
America or during usual vacation periods or periods of illness or other
incapacity. In the event that either of the above conditions is not fulfilled,
the Participant shall forfeit all rights to any unexercised Option held on the
date of the breach of condition. Any determination by the Board of the Company,
which shall act upon the recommendation of the Chairman, that the Participant
is, or has, engaged in a competitive business or activity as aforesaid or has
not been available for consultations as aforesaid shall be conclusive.




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3.5   AMENDMENT, SUSPENSION AND TERMINATION OF PLAN:

      (a)   The Board may suspend or terminate the Plan or any portion thereof
at any time and may amend it from time to time in such respects as the Board may
deem advisable in order that any Options thereunder shall conform to or
otherwise reflect any change in applicable laws or regulations, or to permit the
Company or the Participants to enjoy the benefits of any change in applicable
law or regulations, or in any other respect the Board may deem to be in the best
interests of the Company; provided, however, that any amendment shall be subject
to the approval of the stockholders of the Company at or before the next annual
meeting of the Stockholders if such stockholder approval is required by the
Code, any federal or state law as regulation, the rule of any stock exchange or
automated quotation system on which the Shares maybe listed or quoted, or if the
Board in its discretion, determines to submit such changes to the Plan to its
Stockholders for approval. No such amendment, suspension or termination shall
(A) impair the rights of Participants under outstanding Options without the
consent of the Participants affected thereby or (B) make any change that would
disqualify the Plan, or any other plan of the Company intended to be so
qualified, from the exemption period provided by Rule 16b-3 promulgated under
the Securities Exchange Act of 1934 (the "Exchange Act").

      (b)   The Committee may amend or modify any outstanding Options, in any
manner to the extent that the Committee would have had the authority under the
Plan to initially award such Options, as so modified or amended, including,
without limitation, to change the date or dates as of which such Options may be
exercised. No such amendment or modification shall impair the rights of any
Participant under any such Option without the consent of such Participant.

3.6   DEFINITIONS AND OTHER GENERAL PROVISIONS:

      (a)   The term "disability" as used under the Plan shall mean a finding by
the Committee that a Participant is fully and permanently unable to serve as an
SAB Member of the Company or otherwise unable to perform services on the
Company's behalf because of a physical or mental disability.

      (b)   The term "Fair Market Value" as it relates to Common Stock on any
given date means (i) the mean of the high and low sales prices of the Company's
Common Stock as reported by the Composite Tape of the New York Stock Exchange
(or, if not so reported, on any domestic stock exchanges on which the Common
Stock is then listed); or (ii) if the Common Stock is not listed on any domestic
stock exchange, the mean of the high and low sales prices of the Company's
Common Stock as reported by the National Association of Securities Dealers
Automated Quotation System (or, if not so reported, by the system then regarded
as the most reliable source of such quotations) or, if there are no reported
sales on such date, the mean of the closing bid and asked prices as so reported;
or, (iii) if the Common Stock is listed on a domestic exchange or quoted in the
domestic over-the-counter market, but there are not reported sales or
quotations, as the case may be, on the given date, the value determined pursuant
to (i) or (ii)





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above using the reported sale prices or quotations on the last previous date on
which so reported; or (iv) if none of the foregoing clauses apply, the fair
value as determined in good faith by the Board or the Committee.

      (c)   The term "cause" as used under the Plan shall be deemed to include
(but shall not be limited to) wrongful appropriation of funds of the Company,
divulging confidential information about the Company to the public, the
commission of a gross misdemeanor or felony, or the performance of any similar
action that the Board or the Committee, in their sole discretion, may deem to be
sufficiently injurious to the interests of the Company to constitute substantial
cause for termination. The determination of the Board or the Committee as to the
existence of cause shall be conclusive and binding upon the Participant and the
Company.

3.7   LISTING, REGISTRATION AND LEGAL COMPLIANCE:

      Each Option shall be subject to the requirement that if at any time the
Committee shall determine, in its discretion, that the listing, registration or
qualification of such Option, or any shares of Common Stock or other property
subject thereto, upon any securities exchange or under any foreign, federal or
state securities or other law or regulation, or the consent or approval of any
governmental body or the taking of any other action to comply with or otherwise
with respect to any such law or regulation, is necessary or desirable as a
condition to or in connection with the granting of such Option or the issue,
delivery or purchase of shares of Common Stock or other property thereunder, no
such Option may be exercised or paid in Common Stock or other property unless
such listing, registration, qualification, consent, approval or other action
shall have been effected or obtained free of any conditions not acceptable to
the Committee and the holder of the Option will supply the Company with such
certificates, representations and information as the Company shall request and
shall otherwise cooperate with the Company in effecting or obtaining such
listing, registration, qualification, consent, approval or other action. In the
case of persons subject to Section 16(b) of the Exchange Act, the Committee may
at any time impose any limitations upon the exercise, delivery or payment of any
Option which, in the discretion of the Committee, are necessary or desirable in
order to comply with said Section 16(b) and the rules and regulations
thereunder. If the Company, as part of an offering of securities or otherwise,
finds it desirable because of foreign, federal or state legal or regulatory
requirements to reduce the period during which Options may be exercised, the
Committee may, in its discretion and without the holders' consent, so reduce
such period on not less than 15 days written notice to the holders thereof.

3.8   LOANS:

      The Committee may provide for the Company to make loans to finance the
exercise of any Option as well as the estimated or actual amount of any taxes
payable by the holder as a result of the exercise or payment of any Option and
may prescribe, or may empower the





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Company to prescribe, the other terms and conditions (including but not limited
to the interest rate, maturity date and whether the loan will be secured or
unsecured) of any such loan.

3.9   INDEMNIFICATION:

      Each person who is or shall have been a member of the Committee shall be
indemnified and held harmless by the Company against and from any loss, cost,
liability, or expense that may be imposed upon or reasonably incurred by him in
connection with or resulting from any claim, action, suit, or proceeding to
which he may be a party or in which he may be involved by reason of any action
taken or failure to act under the Plan and against and from any and all amounts
paid by him in settlement thereof, with the Company's approval, or paid by him
in satisfaction of any judgment in any such action, suit, or proceeding against
him, provided he shall give the Company an opportunity, at its own expense, to
handle and defend the same before he undertakes to handle and defend it on his
own behalf. The foregoing right of indemnification shall not be exclusive of any
other rights of indemnification to which such persons may be entitled under the
Company's Amended and Restated Articles of Incorporation, as amended or Bylaws,
as amended, as a matter of law, or otherwise, or any power that the Company may
have to indemnify them or hold them harmless.

3.10  BENEFICIARY DESIGNATION:

      Each Participant under the Plan may name, from time to time, any
beneficiary or beneficiaries (who may be named contingently or successively) to
whom any benefit under the Plan is to be paid in case of his death before he
receives any or all of such benefit. Each designation will revoke all prior
designations by the same Participant, shall be in a form prescribed by the
Committee, and will be effective only when filed by the Participant in writing
with the Committee during his lifetime. In the absence of any such designation,
benefits remaining unpaid at the Participant's death shall be paid to his
estate.

3.11  RIGHTS OF PARTICIPANTS:

      Nothing in the Plan shall interfere with or limit in any way the right
of the Stockholders to terminate the services of any Participant as an SAB
Member of otherwise as a consultant of the Company, nor confer upon any
Participant any right to continue as an SAB Member or other consultant of the
Company for any period of time.

3.12  REQUIREMENTS OF LAW, GOVERNING LAW:

      The granting of Options and the issuance of shares of Common Stock
shall be subject to all applicable laws, rules and regulations, and to such
approvals by any governmental agencies or national securities exchanges as may
be required. The Plan, and all agreements hereunder, shall be construed in
accordance with and governed by the laws of the State of California. The




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provisions of the Plan shall be interpreted so as to comply with the conditions
or requirements of Rule 16b-3 under the Exchange Act, unless a contrary
interpretation of any such provisions is otherwise required by applicable law.

3.13  EFFECTIVE DATE:

      This Stock Option Plan, having been approved by the Board shall be
deemed effective as of May 24, 1999. No awards of Options shall be made
hereunder after May 23, 2009.








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