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                                                                    Exhibit 10.4
                              LUMINEX CORPORATION

                         2000 LONG-TERM INCENTIVE PLAN

                     ARTICLE 1.  ESTABLISHMENT AND PURPOSE

     1.1    Establishment.  Luminex Corporation, a Delaware corporation, hereby
establishes the Luminex Corporation 2000 Long-Term Incentive Plan, as set forth
in this document.

     1.2    Purpose.  The purposes of the Plan are to attract able persons to
enter the employ of the Company, to encourage Employees to remain in the employ
of the Company and to provide motivation to Employees to put forth maximum
efforts toward the continued growth, profitability and success of the Company,
by providing incentives to such persons through the ownership and performance of
the Common Stock of Luminex.  A further purpose of the Plan is to provide a
means through which the Company may attract able persons to become directors,
consultants and independent contractors of the Company and to provide such
individuals with incentive and reward opportunities.  Toward these objectives,
Awards may be granted under the Plan to Employees, Consultants and Outside
Directors on the terms and subject to the conditions set forth in the Plan.

     1.3    Effectiveness.  The Plan shall become effective as of February 4,
2000, the date of its adoption by the Board, provided it is duly approved by the
holders of at least a majority of the shares of Common Stock present or
represented and entitled to vote at a meeting of the stockholders of Luminex
duly held in accordance with applicable law within twelve months after the date
of adoption of the Plan by the Board.  If the Plan is not so approved, the Plan
shall terminate and any Award granted hereunder shall be null and void.

                            ARTICLE 2.  DEFINITIONS

     2.1    Affiliate. "Affiliate" means a "parent corporation" or a "subsidiary
corporation" of Luminex, as those terms are defined in Section 424(e) and (f) of
the Code.

     2.2    Award.  "Award" means any Option, SAR, Restricted Stock, Dividend
Equivalent or Other Incentive Award granted under the Plan, whether singly, in
combination or in tandem, to a Participant.

     2.3    Award Agreement. "Award Agreement" means a written agreement between
Luminex and a Participant that sets forth the terms, conditions, restrictions
and/or limitations applicable to an Award.

     2.4    Board.  "Board" means the Board of Directors of Luminex.

     2.5    Code. "Code" means the Internal Revenue Code of 1986, as amended
from time to time, including regulations thereunder and successor provisions and
regulations thereto.
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     2.6    Committee. "Committee" means the Compensation Committee of the
Board, or such other Committee of the Board as may be designated by the Board to
administer the Plan; provided that the Committee shall consist of two or more
directors of Luminex, all of whom are both a "Non-Employee Director" within the
meaning of Rule 16b-3 under the Exchange Act and an "outside director" within
the meaning of the definition of such term as contained in Treasury Regulation
Section 1.162-27(e)(3) interpreting Section 162(m) of the Code, or any successor
definitions adopted. The members of the Committee shall be appointed from time
to time by, and shall serve at the discretion of, the Board.

     2.7    Common Stock. "Common Stock" means the Common Stock, par value $.001
per share, of Luminex, or any stock or other securities of Luminex hereafter
issued or issuable in substitution or exchange for the Common Stock.

     2.8    Company.  "Company" means Luminex and its Affiliates.

     2.9    Consultant.  "Consultant" means any individual who performs services
for and is treated by Luminex or an Affiliate as an independent contractor for
employment tax purposes, but shall not include an Outside Director.

     2.10   Dividend Equivalents.  "Dividend Equivalents" means an Award granted
to a Participant pursuant to Article 10.

     2.11   Effective Date.  "Effective Date" means the date an Award is
determined to be effective by the Board upon the grant of such Award.

     2.12   Employee.  "Employee" means any person treated as an employee by
Luminex or an Affiliate.  "Employee" shall not include a Consultant or an
Outside Director.

     2.13   Exchange Act.  "Exchange Act" means the Securities Exchange Act of
1934, as amended.

     2.14   Fair Market Value.  "Fair Market Value" means the closing sale price
per share on the date in question, or if no reported sale on such date, on the
last preceding date on which any reported sale occurred of the Common Stock on
the Nasdaq National Market or any national stock exchange or, if the Common
Stock is not traded publicly, the fair market value per share as determined in
good faith by the Board.

     2.15   Incentive Stock Option. "Incentive Stock Option" means an Option
that is intended to meet the requirements of Section 422(b) of the Code.

     2.16   Luminex. "Luminex" means Luminex Corporation, a Delaware
corporation, and any successor thereto.

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     2.17   Nonqualified Stock Option.  "Nonqualified Stock Option" means an
Option that is not intended to meet the requirements of Section 422(b) of the
Code.

     2.18   Option.  "Option" means an option to purchase shares of Common Stock
granted to a Participant pursuant to Article 7, and includes both Incentive
Stock Options and Nonqualified Stock Options.

     2.19   Other Incentive Award. "Other Incentive Award" means an Award
granted to a Participant pursuant to Article 11.

     2.20   Outside Director. "Outside Director" means a member of the Board who
is not also an Employee.

     2.21   Participant. "Participant" means any Employee, Consultant or Outside
Director to whom an Award has been granted under the Plan.

     2.22   Plan. "Plan" means this Luminex Corporation 2000 Long-Term Incentive
Plan.

     2.23   Restricted Stock.  "Restricted Stock" means an Award of shares of
Common Stock granted to a Participant pursuant to, and with such restrictions as
are imposed under, Article 9.  Restricted Stock shall constitute issued and
outstanding shares of Common Stock for all corporate purposes.

     2.24   SARs. "SARs" means an Award of stock appreciation rights granted to
a Participant pursuant to Article 8.

                        ARTICLE 3.  PLAN ADMINISTRATION

     3.1    Plan Administration.  The Plan shall be administered by the Board.
The Board may delegate responsibility for administration of the Plan to a
Committee appointed by and serving at the pleasure of the Board, under such
terms and conditions as the Board shall determine.  Any reference to the Board
in the Plan (other than references to the Board in Article 13) shall be
construed as a reference to the Committee if the Board shall have delegated
responsibility for administration of the Plan to a Committee.

     3.2    Authority of Administrator. The Board shall have total and exclusive
responsibility to control, operate, manage and administer the Plan in accordance
with its terms. The Board shall have all the authority that may be necessary or
helpful to enable it to discharge its responsibilities with respect to the Plan.
Without limiting the generality of the preceding sentence, the Board shall have
the exclusive right to: (i) interpret the Plan and the Award Agreements executed
hereunder; (ii) determine eligibility for participation in the Plan; (iii)
decide all questions concerning eligibility for, and the amount of, Awards
payable under the

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Plan; (iv) construe any ambiguous provision of the Plan or any Award Agreement;
(v) prescribe the form of the Award Agreements embodying Awards granted under
the Plan; (vi) correct any defect, supply any omission or reconcile any
inconsistency in the Plan or any Award Agreement; (vii) issue administrative
guidelines as an aid to administer the Plan and make changes in such guidelines
as it from time to time deems proper; (viii) make regulations for carrying out
the Plan and make changes in such regulations as it from time to time deems
proper; (ix) determine whether Awards should be granted singly, in combination
or in tandem; (x) to the extent permitted under the Plan, grant waivers of Plan
terms, conditions, restrictions and limitations; (xi) accelerate the exercise,
vesting or payment of an Award when such action or actions would be in the best
interests of the Company; (xii) grant Awards in replacement of Awards previously
granted under the Plan or any other employee benefit plan of the Company; and
(xiii) take any and all other actions it deems necessary or advisable for the
proper operation or administration of the Plan.

     3.3    Discretionary Authority.  The Board shall have full discretionary
authority in all matters related to the discharge of its responsibilities and
the exercise of its authority under the Plan, including, without limitation, its
construction of the terms of the Plan and its determination of eligibility for
participation and Awards under the Plan.  The decisions of the Board and its
actions with respect to the Plan shall be final, conclusive and binding on all
persons having or claiming to have any right or interest in or under the Plan,
including Participants and their respective estates, beneficiaries and legal
representatives.

     3.4    Liability; Indemnification. No member of the Board nor any person to
whom authority has been delegated, shall be personally liable for any action,
interpretation or determination made in good faith with respect to the Plan or
Awards granted hereunder, and each member of the Board (or delegatee of the
Board) shall be fully indemnified and protected by Luminex with respect to any
liability he or she may incur with respect to any such action, interpretation or
determination, to the extent permitted by applicable law.

     3.5    Public Company.  From and after such time as the Luminex registers a
class of equity securities under Section 12 of the Exchange Act, it is intended
that this Plan be administered in accordance with the disinterested
administration requirements of Rule 16b-3 promulgated by the Securities and
Exchange Commission, or any successor rule thereto.  With respect to persons
subject to Section 16 of the Exchange Act, if any, transactions under the Plan
are intended to comply with the applicable conditions of Rule 16b-3, or any
successor rule thereto.  Notwithstanding the above, it shall be the
responsibility of such persons, not Luminex, the Board or the Committee, to
comply with the requirements of Section 16 of the Exchange Act.

                            ARTICLE 4.  ELIGIBILITY

     All Employees, Consultants and Outside Directors are eligible to
participate in the Plan. The Board shall recommend, from time to time,
Participants from those Employees, Consultants and Outside Directors who, in the
opinion of the Board, can further the Plan purposes.  Once a

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Participant is recommended for an Award by the Board, the Board shall determine
the type and size of Award to be granted to the Participant and shall establish
in the related Award Agreement the terms, conditions, restrictions and/or
limitations applicable to the Award, in addition to those set forth in the Plan
and the administrative rules and regulations, if any, established by the Board.

                           ARTICLE 5.  FORM OF AWARDS

     Awards may, at the Board's sole discretion, be granted under the Plan in
the form of Options pursuant to Article 7, SARs pursuant to Article 8,
Restricted Stock pursuant to Article 9, Dividend Equivalents pursuant to Article
10, Other Incentive Awards pursuant to Article 11 or a combination thereof.  All
Awards shall be subject to the terms, conditions, restrictions and limitations
of the Plan.  The Board may, in its sole judgment, subject any Award to such
other terms, conditions, restrictions and/or limitations (including, but not
limited to, the time and conditions of exercise, vesting or payment of an Award
and restrictions on transferability of any shares of Common Stock issued or
delivered pursuant to an Award), provided they are not inconsistent with the
terms of the Plan.  Awards under a particular Article of the Plan need not be
uniform, and Awards under two or more Articles of the Plan may be combined into
a single Award Agreement.  Any combination of Awards may be granted at one time
and on more than one occasion to the same Participant.

                     ARTICLE 6.  SHARES SUBJECT TO THE PLAN

     6.1    Available Shares.  The maximum number of shares of Common Stock that
shall be available for grant of Awards under the Plan shall not exceed a total
of 1,750,000, subject to adjustment as provided in Sections 6.2 and 6.3.  Shares
of Common Stock issued pursuant to the Plan may be shares of original issuance
or treasury shares or a combination of the foregoing, as the Board, in its
discretion, shall from time to time determine.

     6.2    Adjustments for Recapitalizations and Reorganizations.

            (a) The shares with respect to which Awards may be granted under the
     Plan are shares of Common Stock as presently constituted, but if, and
     whenever, prior to the expiration or satisfaction of an Award theretofore
     granted, Luminex shall effect a subdivision or consolidation of shares of
     Common Stock or the payment of a stock dividend on Common Stock without
     receipt of consideration by Luminex, the number of shares of Common Stock
     with respect to which such Award may thereafter be exercised or satisfied,
     as applicable, (i) in the event of an increase in the number of outstanding
     shares shall be proportionately increased, and the exercise price per share
     shall be proportionately reduced, and (ii) in the event of a reduction in
     the number of outstanding shares shall be proportionately reduced, and the
     exercise price per share shall be proportionately increased.

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            (b) If Luminex recapitalizes or otherwise changes its capital
     structure, thereafter upon any exercise or satisfaction, as applicable, of
     an Award theretofore granted the Participant shall be entitled to (or
     entitled to purchase, if applicable) under such Award, in lieu of the
     number of shares of Common Stock then covered by such Award, the number and
     class of shares of stock or other securities to which the Participant would
     have been entitled pursuant to the terms of the recapitalization if,
     immediately prior to such recapitalization, the Participant had been the
     holder of record of the number of shares of Common Stock then covered by
     such Award.

            (c) In the event of changes in the outstanding Common Stock by
     reason of a Corporate Transaction (as hereinafter defined),
     recapitalizations, reorganizations, mergers, consolidations, combinations,
     separations (including a spin-off or other distribution of stock or
     property), exchanges, or other relevant changes in capitalization occurring
     after the date of grant of any Award and not otherwise provided for by this
     Section 6.2, any outstanding Awards and any Award Agreements evidencing
     such Awards shall be subject to adjustment by the Board at its discretion
     as to the number, price and kind of shares or other consideration subject
     to, and other terms of, such Awards to reflect such changes in the
     outstanding Common Stock.

            (d) In the event of any changes in the outstanding Common Stock
     provided for in this Section 6.2, the aggregate number of shares available
     for grant of Awards under the Plan may be equitably adjusted by the Board,
     whose determination shall be conclusive. Any adjustment provided for in
     this Section 6.2 shall be subject to any required stockholder action.

     6.3    Adjustments for Awards.  The Board shall have full discretion to
determine the manner in which shares of Common Stock available for grant of
Awards under the Plan are counted.  Without limiting the discretion of the Board
under this Section 6.3, unless otherwise determined by the Board, the following
rules shall apply for the purpose of determining the number of shares of Common
Stock available for grant of Awards under the Plan:

            (a) Options and Restricted Stock. The grant of Options and
     Restricted Stock shall reduce the number of shares available for grant of
     Awards under the Plan by the number of shares subject to such Award.

            (b) SARs.  The grant of SARs shall not affect the number of shares
     available for grant of Awards under the Plan.

            (c) Dividend Equivalents. The grant of Dividend Equivalents shall
     not affect the number of shares available for grant of Awards under the
     Plan, but such number of shares shall be reduced by any shares issued in
     payment or settlement of Dividend Equivalents.

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            (d) Other Incentive Awards. The grant of an Other Incentive Award in
     the form of Common Stock or that may be paid or settled only in Common
     Stock shall reduce the number of shares available for grant of Awards under
     the Plan by the number of shares subject to such Award. The grant of an
     Other Incentive Award that may be paid or settled only for cash shall not
     affect the number of shares available for grant of Awards under the Plan.
     The grant of an Other Incentive Award that may be paid or settled in either
     Common Stock or cash shall reduce the number of shares available for grant
     of Awards under the Plan by the number of shares subject to such Award.

            (e) Termination. If any Award referred to in paragraphs (a) and (d)
     above (other than an Other Incentive Award that may be paid or settled only
     for cash) is canceled or forfeited, or terminates, expires or lapses, for
     any reason (other than the termination of a Related Option (as defined in
     Section 8.1) upon exercise of its corresponding SARs), the shares then
     subject to such Award shall again be available for grant of Awards under
     the Plan.

            (f) Payment of Exercise Price and Withholding Taxes.  If previously
     acquired shares of Common Stock are used to pay the exercise price of an
     Award, or shares of Common Stock that would be acquired upon exercise of an
     Award are withheld to pay the exercise price of such Award, the number of
     shares available for grant of Awards under the Plan other than Incentive
     Stock Options shall be increased by the number of shares delivered or
     withheld as payment of such exercise price.  If previously acquired shares
     of Common Stock are used to pay withholding taxes payable upon exercise,
     vesting or payment of an Award, or shares of Common Stock that would be
     acquired upon exercise, vesting or payment of an Award are withheld to pay
     withholding taxes payable upon exercise, vesting or payment of such Award,
     the number of shares available for grant of Awards under the Plan other
     than Incentive Stock Options shall be increased by the number of shares
     delivered or withheld as payment of such withholding taxes.

                              ARTICLE 7.  OPTIONS

     7.1    General.  Awards may be granted to Employees, Consultants and
Outside Directors in the form of Options. With respect to Employees, Options
granted under the Plan may be Incentive Stock Options or Nonqualified Stock
Options, or a combination of both; provided, however, that no Incentive Stock
Options shall be granted later than 10 years from the date of adoption of the
Plan by the Board. For Consultants and Outside Directors, these Options may only
be in the form of Nonqualified Stock Options.

     7.2    Terms and Conditions of Options.  An Option shall be exercisable in
whole or in such installments and at such times as may be determined by the
Board.  The price at which a share of Common Stock may be purchased upon
exercise of a Nonqualified Stock Option shall be determined by the Board, but
such exercise price shall not be less than 50% of the Fair Market

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Value per share of Common Stock on the Effective Date of the Option's grant;
provided, however, that, with respect to Options granted to an Outside Director,
such exercise price shall not be less than the Fair Market Value per share of
Common Stock on the Effective Date of the Option's grant. Except as otherwise
provided in Section 7.3, the term of each Option shall be as specified by the
Board; provided, however, that unless otherwise designated by the Board, no
Options shall be exercisable later than 10 years from the Effective Date of the
Option's grant.

     7.3    Restrictions Relating to Incentive Stock Options. Options granted in
the form of Incentive Stock Options shall, in addition to being subject to the
terms and conditions of Section 7.2, comply with Section 422(b) of the Code.
Accordingly, to the extent that the aggregate Fair Market Value (determined at
the time the respective Incentive Stock Option is granted) of Common Stock with
respect to which Incentive Stock Options are exercisable for the first time by
an individual during any calendar year under all incentive stock option plans of
Luminex and its Affiliates exceeds $100,000, such excess Incentive Stock Options
shall be treated as options which do not constitute Incentive Stock Options. The
price at which a share of Common Stock may be purchased upon exercise of an
Incentive Stock Option shall be determined by the Board, but such exercise price
shall not be less than 100% of the Fair Market Value of a share of Common Stock
on the Effective Date of the Option's grant. No Incentive Stock Option shall be
granted to an Employee under the Plan if, at the time such Option is granted,
such Employee owns stock possessing more than 10% of the total combined voting
power of all classes of stock of Luminex or an Affiliate, within the meaning of
Section 422(b)(6) of the Code, unless (i) on the Effective Date of grant of such
Option, the exercise price of such Option is at least 110% of the Fair Market
Value of the Common Stock subject to the Option and (ii) such Option by its
terms is not exercisable after the expiration of five years from the Effective
Date of the Option's grant.

     7.4    Additional Terms and Conditions.  The Board may subject any Award of
an Option to such other terms, conditions, restrictions and/or limitations as it
determines are necessary or appropriate, provided they are not inconsistent with
the Plan.

     7.5    Exercise of Options. Subject to the terms and conditions of the
Plan, Options shall be exercised by the delivery of a written notice of exercise
to Luminex, setting forth the number of shares of Common Stock with respect to
which the Option is to be exercised, accompanied by full payment for such
shares.

     The exercise price of an Option shall become immediately due upon exercise
of the Option and shall, subject to the provisions of the documents evidencing
the Option, be payable in cash or check made payable to Luminex.  Should the
Common Stock be registered under Section 12 of the Exchange Act at the time the
Option is exercised, then the exercise price may also be paid as follows:

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                (i)   in shares of Common Stock held for the requisite period of
     time necessary to avoid a charge to Luminex's earnings for financial
     reporting purposes and valued at Fair Market Value on the date of exercise
     at the discretion of the Committee; or

                (ii)  to the extent the Option is exercised for shares of Common
     Stock that are not subject to restrictions (other than restrictions imposed
     under applicable federal and state securities laws), through a special sale
     and remittance procedure pursuant to which the optionee shall concurrently
     provide irrevocable instructions (A) to a brokerage firm designated by
     Luminex to effect the immediate sale of the purchased shares and remit to
     Luminex, out of the sale proceeds available on the settlement date,
     sufficient funds to cover the aggregate exercise price payable for the
     purchased shares plus all applicable federal, state and local income and
     employment taxes required to be withheld by Luminex or an Affiliate by
     reason of such exercise and (B) to Luminex to deliver the certificates for
     the purchased shares directly to such brokerage firm in order to complete
     the sale.

     In addition, any grant of a Nonqualified Stock Option under the Plan may,
at the discretion of the Board, provide that payment of the exercise price of
the Nonqualified Stock Option may also be made in whole or in part in the form
of shares of Restricted Stock or other shares of Common Stock that are subject
to risk of forfeiture or restrictions on transfer.  Unless otherwise determined
by the Board at the time of grant of such Nonqualified Stock Option, whenever
the exercise price of such Nonqualified Stock Option is paid in whole or in part
by means of the form of consideration specified in the immediately preceding
sentence, the shares of Common Stock received by the Participant upon the
exercise of such Nonqualified Stock Option shall be subject to the same risk of
forfeiture and restrictions on transfer as those that applied to the
consideration surrendered by the Participant.  However, the risk of forfeiture
and restrictions on transfer shall apply only to the same number of shares of
Common Stock received by the Participant upon exercise as applied to the
forfeitable or restricted Common Stock surrendered by the Participant in payment
of the exercise price.

     As soon as reasonably practicable after receipt of written notification of
exercise of an Option and full payment of the exercise price and any required
withholding taxes, Luminex shall deliver to the Participant, in the
Participant's name, a stock certificate or certificates in an appropriate amount
based upon the number of shares of Common Stock purchased under the Option.

     7.6    Termination of Service.  Each Award Agreement embodying the Award of
an Option shall set forth the extent to which the Participant shall have the
right to exercise the Option following termination of the Participant's
employment or service with the Company.  Such provisions shall be determined in
the sole discretion of the Board, need not be uniform among all Options granted
under the Plan and may reflect distinctions based on the reasons for termination
of employment or service.  Subject to Section 6.2 and Article 12, in the event
that a Participant's Award Agreement embodying the Award of an Option does not
set forth such

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termination provisions, the following termination provisions shall apply with
respect to such Award.

            (a) Death or Disability.  If the employment or service of a
     Participant shall terminate by reason of death or permanent and total
     disability (within the meaning of Section 22(e)(3) of the Code),
     outstanding Options held by the Participant may be exercised, to the extent
     then vested, no more than one year from the date of such termination,
     unless the Options, by their terms, expire earlier.

            (b) Other Termination. If the employment or service of a Participant
     shall terminate for any reason other than the reasons set forth in
     paragraph (a) above, whether on a voluntary or involuntary basis,
     outstanding Options held by the Participant may be exercised, to the extent
     then vested, no more than 60 days from the date of such termination, unless
     the Options, by their terms, expire earlier.

            (c) Termination for Cause.  Notwithstanding paragraphs (a) and (b)
     above, if the employment or service of a Participant shall be terminated by
     reason of such Participant's fraud, dishonesty or performance of other acts
     detrimental to the Company, all outstanding Options held by the Participant
     shall immediately be forfeited to the Company and no additional exercise
     period shall be allowed, regardless of the vested status of the Options.

     7.7    Maximum Option Grants. Any provision of the Plan (other than Section
7.8) notwithstanding, the maximum number of shares of Common Stock for which
Options and SARs may be granted under the Plan to any one Employee during a
calendar year is 175,000, subject to adjustment as provided in Sections 6.2 and
6.3.

     7.8    Award of Options to Directors. Notwithstanding anything contained in
the Plan to the contrary, all Options granted to an Outside Director shall be
subject to the following limitations:

            (a) each such Option shall have an exercise price of not less than
     the Fair Market Value of the Common Stock as of the Effective Date of such
     Option's grant;

            (b) the initial grant of an Option to an Outside Directors shall not
     exceed 5,000 shares of Common Stock (subject to adjustment as provided in
     Sections 6.2 and 6.3); and

            (c) following the initial grant of an Option to an Outside
     Directors, the maximum number of shares of Common Stock for which Options
     may be granted to such Outside Director shall not exceed 2,000 shares of
     Common Stock (subject to adjustment as provided in Sections 6.2 and 6.3) in
     any one calendar year.

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                                ARTICLE 8.  SARs

     8.1    General.  The Board may from time to time grant SARs in conjunction
with all or any portion of any Option (the "Related Option") either (i) at the
time of the initial Option grant (not including any subsequent modification that
may be treated as a new grant of an Incentive Stock Option for purposes of
Section 424(h) of the Code) or (ii) with respect to Nonqualified Stock Options,
at any time after the initial Option grant while the Nonqualified Stock Option
is still outstanding.  SARs shall not be granted other than in conjunction with
an Option granted hereunder.  SARs shall not be granted to Outside Directors.

     8.2    Terms and Conditions.  SARs granted hereunder shall comply with the
following conditions and also with the terms of the Award Agreement governing
the Related Option:

            (a) The SAR shall expire no later than the expiration of the Related
     Option.

            (b) Upon the exercise of an SAR, the Participant shall be entitled
     to receive from Luminex or the appropriate Affiliate in cash an amount
     equal to the excess of the aggregate Fair Market Value of the shares of
     Common Stock with respect to which the SAR is then being exercised
     (determined as of the date of such exercise) over the aggregate purchase
     price of such shares as provided in the Related Option.

            (c) SARs shall be exercisable (i) only at such time or times and
     only to the extent that the Related Option shall be exercisable, (ii) only
     when the Fair Market Value of the shares subject to the Related Option
     exceeds the purchase price of the shares as provided in the Related Option,
     and (iii) only upon surrender of the Related Option or any portion thereof
     with respect to the shares for which the SARs are then being exercised.

            (d) Upon the exercise of an SAR, the Related Option shall be deemed
     to have been terminated to the extent of the number of shares of Common
     Stock with respect to which such SARs are exercised. Upon the exercise or
     termination of the Related Option, the SARs with respect to such Related
     Option shall be deemed to have been terminated to the extent of the number
     of shares of Common Stock with respect to which the Related Option was so
     exercised or terminated.

     8.3    Exercise of SARs. Each exercise of SARs, or a portion thereof, shall
be evidenced by a notice in writing to Luminex.

                          ARTICLE 9.  RESTRICTED STOCK

     9.1    General. Awards may be granted to Employees, Consultants and Outside
Directors in the form of Restricted Stock. Restricted Stock shall be awarded in
such numbers and at such times as the Board shall determine.

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     9.2    Restriction Period.  At the time an Award of Restricted Stock is
granted, the Board shall establish a period of time or other triggering event
(the "Restriction Period") applicable to such Restricted Stock.  Each Award of
Restricted Stock may have a different Restriction Period, in the discretion of
the Board.  The Restriction Period applicable to a particular Award of
Restricted Stock shall not be changed except as permitted by Section 6.2,
Section 9.3 or Article 12.

     9.3    Other Terms and Conditions. Restricted Stock awarded to a
Participant under the Plan shall be represented by a stock certificate
registered in the name of the Participant or, at the option of Luminex, in the
name of a nominee of Luminex. Subject to the terms and conditions of the Award
Agreement, a Participant to whom Restricted Stock has been awarded shall have
the right to receive dividends thereon during the Restriction Period, to vote
the Restricted Stock and to enjoy all other stockholder rights with respect
thereto, except that (i) the Participant shall not be entitled to possession of
the stock certificate representing the Restricted Stock until the Restriction
Period shall have expired, (ii) Luminex shall retain custody of the Restricted
Stock during the Restriction Period, (iii) the Participant may not sell,
transfer, pledge, exchange, hypothecate or otherwise dispose of the Restricted
Stock during the Restriction Period and (iv) a breach of the terms and
conditions established by the Board pursuant to the Award of the Restricted
Stock shall cause a forfeiture of the Restricted Stock. At the time of an Award
of Restricted Stock, the Board may, in its sole discretion, prescribe additional
terms, conditions, restrictions and/or limitations applicable to the Restricted
Stock, including, but not limited to, rules pertaining to the termination of
employment or service (by reason of death, permanent and total disability, or
otherwise) of a Participant prior to expiration of the Restriction Period.

     9.4    Payment for Restricted Stock. A Participant shall not be required to
make any payment for Restricted Stock awarded to the Participant, except to the
extent otherwise required by the Board or by applicable law.

     9.5    Miscellaneous. Nothing in this Article 9 shall prohibit the exchange
of shares of Restricted Stock issued under the Plan pursuant to a plan of
reorganization for stock or securities of Luminex or another corporation that is
a party to the reorganization, but the stock or securities so received for
shares of Restricted Stock shall, except as provided in Section 6.2 or Article
12, become subject to the restrictions applicable to the Award of such
Restricted Stock. Any shares of stock received as a result of a stock split or
stock dividend with respect to shares of Restricted Stock shall also become
subject to the restrictions applicable to the Award of such Restricted Stock.

                       ARTICLE 10.  DIVIDEND EQUIVALENTS

     Dividend Equivalents may be granted under the Plan to Employees,
Consultants and Outside Directors, either as a component of another Award or as
a separate Award, subject to such terms, conditions, restrictions and/or
limitations as the Board may establish.  In general, and

                                      -12-
<PAGE>

subject to such terms, conditions, restrictions and/or limitations as the Board
may establish, an Award of Dividend Equivalents shall confer upon the
Participant a right to receive, in the event of a cash or stock dividend or
other distribution paid or made on the outstanding shares of Common Stock, an
amount equal to the dividend or other distribution that would have been received
by the Participant had the shares of Common Stock covered by the Award been
issued and outstanding on the record date established for such dividend or other
distribution. Dividend Equivalents may be paid currently or may be deemed to be
reinvested in additional shares of Common Stock (which may thereafter accrue
additional Dividend Equivalents). Any such reinvestment shall be at the Fair
Market Value of the Common Stock at the time thereof. Dividend Equivalents may
be paid in cash, shares of Common Stock, other Awards or other property, or a
combination thereof, in a single payment or in installments, and at such time or
times as the Board shall determine. Dividend Equivalents granted as a component
of another Award may provide that such Dividend Equivalents shall be paid upon
exercise, payment or settlement of or lapse of restrictions on such other Award,
and that such Dividend Equivalents shall expire or be forfeited under the same
conditions as such other Award. Dividend Equivalents granted as a component of
another Award may also contain terms and conditions different from such other
Award.

                      ARTICLE 11.  OTHER INCENTIVE AWARDS

     Other Incentive Awards may be granted under the Plan to Employees,
Consultants and Outside Directors based upon, payable in or otherwise related
to, in whole or in part, shares of Common Stock if the Board, in its sole
discretion, determines that such Other Incentive Awards are consistent with the
purposes of the Plan.  Subject to the terms and provisions of the Plan, Other
Incentive Awards may be granted to Employees, Consultants and Outside Directors
in such amount, upon such terms and at any time and from time to time as shall
be determined by the Board.  Each grant of an Other Incentive Award shall be
evidenced by an Award Agreement that shall specify the amount of the Other
Incentive Award and the terms, conditions, restrictions and/or limitations
applicable to such Award.  Payment of Other Incentive Awards shall be made at
such times and in such form, which may be cash, shares of Common Stock or other
property (or a combination thereof),a s established by the Board, subject to the
terms of the Plan.

                      ARTICLE 12.  CORPORATE TRANSACTIONS

     12.1   Definition of Corporate Transaction. A "Corporate Transaction" shall
mean any of the following transactions with respect to which Luminex is a party:

            (a) a merger or consolidation in which (i) Luminex is not the
     surviving entity or (ii) Luminex survives only as a subsidiary of an entity
     other than a previously wholly-owned subsidiary of Luminex;

                                      -13-
<PAGE>

            (b) a tender offer or share exchange resulting in the transfer of
     ownership of more than fifty percent (50%) of the total outstanding voting
     power of Luminex immediately after such transaction; or

            (c) the sale, lease, transfer or other disposition of all or
     substantially all of the assets of Luminex (other than to a wholly-owned
     subsidiary of Luminex).

     12.2   Effect on Outstanding Awards.  Notwithstanding anything to the
contrary contained herein, no later than 30 days after (i) the approval by the
stockholders of Luminex of a Corporate Transaction of the type described in
Section 12.1(a) or (c) or (ii) the public announcement of a Corporate
Transaction of the type described in Section 12.1(b), the Board, acting in its
sole discretion without the consent or approval of any Participant, may act to
effect one or more of the following alternatives, which may vary among
individual Participants and which may vary among Awards held by any individual
Participant:

            (a) accelerate the vesting of and the time at which Awards then
     outstanding may be exercised so that such Awards may be exercised in full
     (irrespective of whether such Awards are fully exercisable prior to the
     date of such Corporate Transaction) for a limited period of time on or
     before a specified date fixed by the Board (which date may be before or
     after the date of such Corporate Transaction), after which specified date
     all unexercised Awards and all rights of Participants thereunder shall
     terminate;

            (b) require the mandatory surrender to Luminex by selected
     Participants of some or all of the outstanding Awards held by such
     Participants (irrespective of whether such Awards are fully exercisable
     prior to the date of such Corporate Transaction) as of a date specified by
     the Board (which date may be before or after the date of such Corporate
     Transaction), in which event the Board shall thereupon cancel such Awards
     and Luminex shall pay to each Participant an amount of cash per share equal
     to the excess, if any, of the following amount, whichever is applicable:

                (i)    the per share price offered to stockholders of Luminex in
          a merger or consolidation transaction described in Section 12.1(a),
          less the applicable exercise price payable by Participant pursuant to
          such Award;

                (ii)   the price per share offered to stockholders of Luminex in
          a tender offer or share exchange described in Section 12.1(b), less
          the applicable exercise price payable by Participant pursuant to such
          Award;

                (iii)  if such Corporate Transaction occurs pursuant to a type
          of transaction described in Section 12.1(c), the Fair Market Value per
          share of Common Stock subject to such Award, as determined by the
          Board as of the date determined by the Board to be the date of such
          transaction, less the applicable exercise price, if any, payable by
          the Participant pursuant to such Award.

                                      -14-
<PAGE>

     In the event that the consideration offered to stockholders of Luminex in
     any Corporate Transaction consists of anything other than cash, the Board
     shall determine the fair cash equivalent of the portion of the
     consideration offered which is other than cash.

            (c) make such adjustments to Awards then outstanding so that such
     Awards thereafter cover the number and class of shares of stock or other
     securities or property (including, without limitation, cash) to which the
     Participant would have been entitled pursuant to the terms of the Corporate
     Transaction had the Participant been the holder of record of the number of
     shares of Common Stock covered by such Award; or

            (d) in the event of a Corporate Transaction in which the holders of
     Luminex's Common Stock receive shares of stock in the acquiring entity
     ("Acquiror Stock"), convert Awards into Awards to acquire shares of
     Acquiror Stock ("Substitute Awards").  Each Substitute Award shall be
     exercisable on substantially the same terms and conditions contained in the
     applicable Award, and shall cover such number of shares of Acquiror Stock
     and have such exercise price and other terms as the Board shall, in its
     discretion, deem appropriate in order to approximate with the Substitute
     Award an economic equivalent to the applicable Award.

In the event of Corporate Transaction, the Board may, but shall not be required
to, take any such action set forth in Sections 12.3(a) through (d) above or
shall be permitted to allow any or all outstanding Awards to remain so
outstanding in accordance with the terms and conditions of the related Award
Agreement.

                     ARTICLE 13.  AMENDMENT AND TERMINATION

     The Board may at any time suspend, terminate, amend or modify the Plan, in
whole or in part; provided, however, that no amendment or modification of the
Plan shall become effective without the approval of such amendment or
modification by the stockholders of Luminex if such amendment or modification
(i) increases the maximum number of shares subject to the Plan or (ii) changes
the designation or class of persons eligible to receive Awards under the Plan
unless counsel for Luminex determines that such approval is otherwise required
by applicable law.  Upon termination of the Plan, the terms and provisions of
the Plan shall, notwithstanding such termination, continue to apply to Awards
granted prior to such termination.   No suspension, termination, amendment or
modification of the Plan shall adversely affect in any material way any Award
previously granted under the Plan, without the consent of the Participant
holding such Award.

     Except as otherwise provided in Article 12, the Board may amend the terms
of any outstanding Award granted pursuant to this Plan, but any amendment that
would adversely affect the Participant's rights under an outstanding Award shall
not be made without the written consent of the Participant.  The Board may, with
a Participant's written consent, cancel any outstanding Award or accept any
outstanding Award in exchange for a new Award.

                                      -15-
<PAGE>

                           ARTICLE 14.  MISCELLANEOUS

     14.1   Award Agreements.  After the Board grants an Award under the Plan to
a Participant, Luminex and the Participant shall enter into an Award Agreement
setting forth the terms, conditions, restrictions and/or limitations applicable
to the Award and such other matters as the Board may determine to be
appropriate. The terms and provisions of the respective Award Agreements need
not be identical. All Award Agreements shall be subject to the provisions of the
Plan. In the event of any conflict between an Award Agreement and the Plan, the
terms of the Plan shall govern.

     14.2   Additional Conditions.  Notwithstanding anything in the Plan to the
contrary: (i) Luminex may, if it shall determine it necessary or desirable for
any reason, at the time of grant of any Award or the issuance of any shares of
Common Stock pursuant to any Award, require the recipient of the Award or such
shares of Common Stock, as a condition to the receipt thereof, to deliver to
Luminex a written representation of present intention to acquire the Award or
such shares of Common Stock for his or her own account for investment and not
for distribution; and (ii) if at any time Luminex further determines, in its
sole discretion, that the listing, registration or qualification (or any
updating of any such document) of any Award or shares of Common Stock issuable
pursuant thereto is necessary on any securities exchange or market or under any
federal or state securities or blue sky laws, or that the consent or approval of
any governmental or regulatory body is necessary or desirable as a condition of,
or in connection with, the grant of any Award, the issuance of shares of Common
Stock pursuant thereto or the removal of any restrictions imposed on such
shares, such Award shall not be awarded or such shares of Common Stock shall not
be issued or such restrictions shall not be removed, as the case may be, in
whole or in part, unless such listing, registration, qualification, consent or
approval shall have been effected or obtained free of any conditions not
acceptable to Luminex.

     14.3   Legends on Stock Certificates.  Unless the shares of Common Stock
issued pursuant to an Award shall have been registered under the Securities Act
of 1933, as amended, each certificate representing such shares shall have
conspicuously stamped, printed or typed on the face or back thereof the
following legend:

            THE SHARES EVIDENCED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR
            INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
            1933 OR APPLICABLE STATE SECURITIES LAWS AND MAY NOT BE SOLD OR
            OTHERWISE TRANSFERRED UNLESS SUCH SHARES ARE FIRST REGISTERED
            THEREUNDER OR UNLESS THE COMPANY RECEIVES A WRITTEN OPINION OF
            COUNSEL, WHICH OPINION AND COUNSEL ARE ACCEPTABLE TO THE COMPANY, TO
            THE EFFECT THAT REGISTRATION THEREUNDER IS NOT REQUIRED.

                                      -16-
<PAGE>

     14.4   Nonassignability.  Except as otherwise provided in the Award
Agreement, no Award granted under the Plan may be sold, transferred, pledged,
exchanged, hypothecated or otherwise disposed of, other than by will or pursuant
to the applicable laws of descent and distribution.  Further, no such Award
shall be subject to execution, attachment or similar process. Any attempted
sale, transfer, pledge, exchange, hypothecation or other disposition of an Award
not specifically permitted by the Plan or the Award Agreement shall be null and
void and without effect.  All Awards granted to a Participant under the Plan
shall be exercisable during his or her lifetime only by such Participant or, in
the event of the Participant's legal incapacity, by his or her guardian or legal
representative.

     14.5   Withholding Taxes.  The Company shall be entitled to deduct from any
payment made under the Plan, regardless of the form of such payment, the amount
of all applicable income and employment taxes required by law to be withheld
with respect to such payment, may require the Participant to pay to the Company
such withholding taxes prior to and as a condition of the making of any payment
or the issuance or delivery of any shares of Common Stock under the Plan and
shall be entitled to deduct from any other compensation payable to the
Participant any withholding obligations with respect o Awards under the Plan.
In accordance with any applicable administrative guidelines it establishes, the
Board may allow a Participant to pay the amount of taxes required by law to be
withheld from or with respect to an Award by (i) withholding shares of Common
Stock from any payment of Common Stock due as a result of such Award or (ii)
permitting the Participant to deliver to the Company previously acquired shares
of Common Stock held for the requisite period of time necessary to avoid a
charge to Luminex's earnings for financial reporting purposes, in each case
having a Fair Market Value equal to the amount of such required withholding
taxes.  No payment shall be made and no shares of Common Stock shall be issued
pursuant to any Award unless and until the applicable tax withholding
obligations have been satisfied.

     14.6   No Fractional Shares.  No fractional shares of Common Stock shall be
issued or delivered pursuant to the Plan or any Award granted hereunder, and no
payment or other adjustment shall be made in respect of any such fractional
share.

     14.7   Notices.  All notices required or permitted to be given or made
under the Plan or any Award Agreement shall be in writing and shall be deemed to
have been duly given or made if (i) delivered personally, (ii) transmitted by
first class registered or certified United States mail, postage prepaid, return
receipt requested, (iii) sent by prepaid overnight courier service or (iv) sent
by telecopy or facsimile transmission, answer back requested, to the person who
is to receive it at the address that such person has theretofore specified by
written notice delivered in accordance herewith. Such notices shall be effective
(i) if delivered personally or sent by courier service, upon actual receipt by
the intended recipient, (ii) if mailed, upon the earlier of five days after
deposit in the mail or the date of delivery as shown by the return receipt
therefor or (iii) if sent by telecopy or facsimile transmission, when the answer
back is received. Luminex or a Participant may change, at any time and from time
to time, by written notice to the other, the address that it or such Participant
had theretofore specified for receiving notices. Until such address is changed
in accordance herewith, notices hereunder or under an Award Agreement

                                      -17-
<PAGE>

shall be delivered or sent (i) to a Participant at his or her address as set
forth in the records of the Company or (ii) to Luminex at the principal
executive offices of Luminex clearly marked "Attention:  John Dapper".

     14.8   Binding Effect.  The obligations of Luminex under the Plan shall be
binding upon any successor corporation or organization resulting from the
merger, consolidation or other reorganization of Luminex, or upon any successor
corporation or organization succeeding to all or substantially all of the assets
and business of Luminex.  The terms and conditions of the Plan shall be binding
upon each Participant and his or her heirs, legatees, distributees and legal
representatives.

     14.9   Severability.  If any provision of the Plan or any Award Agreement
is held to be illegal or invalid for any reason, the illegality or invalidity
shall not affect the remaining provisions of the Plan or such agreement, as the
case may be, but such provision shall be fully severable and the Plan or such
agreement, as the case may be, shall be construed and enforced as if the illegal
or invalid provision had never been included herein or therein.

     14.10  No Restriction of Corporate Action.  Nothing contained in the Plan
shall be construed to prevent Luminex or any Affiliate from taking any corporate
action (including any corporate action to suspend, terminate, amend or modify
the Plan) that is deemed by Luminex or such Affiliate to be appropriate or in
its best interest, whether or not such action would have an adverse effect on
the Plan or any Awards made or to be made under the Plan.  No Participant or
other person shall have any claim against Luminex or any Affiliate as a result
of such action.

     14.11  Governing Law.  The Plan shall be governed by and construed in
accordance with the internal laws (and not the principles relating to conflicts
of laws) of the State of Delaware, except as superseded by applicable federal
law.

     14.12  No Right, Title or Interest in Company Assets.  No Participant shall
have any rights as a stockholder of Luminex as a result of participation in the
Plan until the date of issuance of a stock certificate in his or her name and,
in the case of Restricted Stock, unless and until such rights are granted to the
Participant under the Plan.  To the extent any person acquires a right to
receive payments from the Company under the Plan, such rights shall be no
greater than the rights of an unsecured creditor of the Company, and such person
shall not have any rights in or against any specific assets of the Company.  All
of the Awards granted under the Plan shall be unfunded.

     14.13  Risk of Participation.  Nothing contained in the Plan shall be
construed either as a guarantee by Luminex or its Affiliates, or their
respective stockholders, directors, officers or employees, of the value of any
assets of the Plan or as an agreement by Luminex or its Affiliates, or their
respective stockholders, directors, officers or employees, to indemnify anyone
for any losses, damages, costs or expenses resulting from participation in the
Plan.

                                      -18-
<PAGE>

     14.14  No Guarantee of Tax Consequences.  No person connected with the Plan
in any capacity, including, but not limited to, Luminex and the Affiliates and
their respective directors, officers, agents and employees, makes any
representation, commitment or guarantee that any tax treatment, including, but
not limited to, federal, state and local income, estate and gift tax treatment,
will be applicable with respect to any Awards or payments thereunder made to or
for the benefit of a Participant under the Plan or that such tax treatment will
apply to or be available to a Participant on account of participation in the
Plan.

     14.15  Other Benefits.  No Award granted under the Plan shall be considered
compensation for purposes of computing benefits or contributions under any
retirement plan of Luminex or any Affiliate, nor affect any benefits or
compensation under any other benefit or compensation plan of Luminex or any
Affiliate now or subsequently in effect.

     14.16  Continued Employment or Service.  Nothing contained in the Plan or
in any Award Agreement shall confer upon any Participant the right to continue
in the employ or service of the Company, or interfere in any way with the rights
of the Company to terminate his or her employment or service at any time, with
or without cause.

     14.17  Miscellaneous.  Headings are given to the articles and sections of
the Plan solely as a convenience to facilitate reference. Such headings shall
not be deemed in any way material or relevant to the construction of the Plan or
any provisions hereof. The use of the masculine gender shall also include within
its meaning the feminine. Wherever the context of the Plan dictates, the use of
the singular shall also include within its meaning the plural, and vice versa.

     IN WITNESS WHEREOF, this Plan has been executed as of February 4, 2000.


                                 LUMINEX CORPORATION


                                 By:
                                      -----------------------------------------
                                      Mark Chandler, Chief Executive Officer

                                      -19-