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                                                                   EXHIBIT 10.31

                              EMPLOYMENT AGREEMENT

            THIS EMPLOYMENT AGREEMENT made as of the first day of February,
2002.

B E T W E E N

            VISIBLE GENETICS INC., a corporation duly
            incorporated under the laws of the Province
            of Ontario and having its head office in the
            City of Toronto, in the Province of Ontario

            hereinafter referred to as the "VGI"

            - and -

            VISIBLE GENETICS CORPORATION, a
            corporation duly incorporated under the laws
            of the State of Delaware and having its
            principal office in the City of Suwanee in the
            State of Georgia

            hereinafter referred to as the "EMPLOYER"

            - and -

            THOMAS J. CLARKE, an individual
            resident in the City of Lilburn, in the State
            of Georgia hereinafter referred to as the
            "EXECUTIVE"

WHEREAS the Executive has been employed by the Employer since December 14, 1999;

AND WHEREAS the Employer and Executive wish to confirm the terms and conditions
of that employment and to set out the terms and conditions of the employment on
an ongoing basis;

AND WHEREAS the Employer is a wholly owned subsidiary of VGI;

The parties agree as follows:

1.     POSITION, DUTIES AND REMUNERATION

1.1    The Executive shall serve as the Chief Financial Officer of the Employer.
       At the request

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       of VGI, the Executive also shall serve as the Chief Financial Officer of
       VG1. The Executive will be paid an annual salary of two hundred twenty
       five thousand dollars (US $225,000) payable in accordance with the
       Employer's normal payroll policy.

1.2    In addition to salary, for the performance of his services hereunder, the
       Executive shall be entitled to participate in all of the Employer's
       benefit plans generally available to its Executives of equal rank,
       including the Employer's bonus plan and the Employer's group, life,
       medical, dental, hospital, long-term disability, accidental death and
       dismemberment insurance benefit plans. In the event the Employer adopts
       any new benefit plans, pensions or perquisites, the Executive shall have
       the right to participate on a basis equivalent to other Executives of
       equal rank to the Employer. All plans shall be administered and governed
       by their respective terms.

1.3    The Executive agrees to perform faithfully the duties inherent in the
       position and all other lawful instructions and duties as the Employer may
       from time to time reasonably require.

1.4    The Executive agrees to use his best efforts to promote the interests of
       the Employer and its affiliates, including VGI, to devote his full time
       and attention to the business of the Employer and VGI and to adhere to
       the instructions and directives of the Employer.

1.5    During the term of his employment, the Executive agrees to refrain from
       engaging in any activity which will in any manner, directly or
       indirectly, compete with the trade or business of VGI or the Employer or
       any other affiliate of VGI.

1.6    During the term of his employment, the Executive agrees not to possess or
       acquire, directly or indirectly, any interest in any firm, partnership,
       association or corporation, the business operations of which will in any
       manner, directly or indirectly, compete with the business of VGI, the
       Employer or any other affiliate of VGI other than as a stockholder
       holding no greater than one per cent (1%) of a public company whose
       shares are listed for trading on a recognized stock exchange or traded on
       the over-the-counter market.

1.7    The Employer agrees in its sole discretion to review the salary and
       benefits payable to Executive hereunder annually.

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1.8    Provided the Executive submits reasonably detailed receipts or other
       supporting documentation to the Employer, the Employer shall reimburse
       the Executive for all proper and reasonable out-of-pocket expenses
       actually incurred by the Executive in the performance of his duties
       hereunder.

2.     EMPLOYMENT CONDITIONS

2.1    The Executive agrees to adhere to and abide by the Employer's policies,
       as amended from time to time, regarding holidays, sick leave, hospital
       insurance, and other fringe benefits.

3.     TERMINATION OF EMPLOYMENT

3.1    This Agreement and the employment of the Executive may be terminated by
       the Employer for any reason upon prior written notice and payment of an
       amount equal to twelve (12) months' salary at the rate in effect at the
       time of termination plus one (1) additional month for each full year of
       employment with the Employer after December 14, 2000, but in no event
       more than a total of eighteen (18) months salary ("Termination Payment").
       Such amount shall be paid as a lump sum payment subject to all statutory
       deductions within thirty (30) days following termination.

3.2    The Executive may be dismissed at any time by the Employer for Cause. For
       purposes of this Article 3, "Cause" means the Executive (a) fails in any
       material respect to perform his obligations hereunder as provided herein,
       provided that such Cause shall not exist unless the Employer shall first
       have provided the Executive with written notice specifying in reasonable
       detail the factors constituting such material failure and such material
       failure shall not have been cured by the Executive within 10 days after
       such notice; (b) has been convicted of a felony or has entered a plea of
       guilty or NOLO CONTENDERE with respect thereto; (c) has committed any act
       in connection with his employment with the Employer which involved fraud,
       misappropriation of funds, or breach of fiduciary duty to the Employer or
       any affiliate thereof; or (d) has breached in any material respect any of
       the provisions of the Confidentiality, Invention Agreement and
       Non-Compete Agreement between the Executive and the Employer dated
       December 14, 1999.

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3.3    The employment of the Executive may be terminated by the Executive for
       any reason upon prior written notice to the Employer of one hundred
       twenty (120) days.

3.4    Unless Article 4 hereof is applicable, upon the termination of this
       Agreement and on termination of the employment of the Executive, whether
       upon notice or otherwise, the Executive shall have no claim against the
       Employer for any further liability to make payments in connection with
       the termination of the Executive's employment, other than those arising
       from this Article 3.

4.     CHANGE OF CONTROL AND RETENTION BENEFITS

4.1    DEFINITIONS.

For the purposes of this Article 4, the following terms shall have the meaning
set out below:

       (a)  "2001 Compensation" shall mean the Executive's gross base salary
            paid to him in calendar year 2001, plus the gross amount of any cash
            bonuses paid to the Executive in calendar year 2001.

       (b)  "Cause" shall mean the Employer's right to terminate the Executive's
            employment on the basis of (i) the Executive's willful and continued
            failure to substantially perform his material duties of employment
            provided that the Employer shall have first provided the Executive
            with written notice specifying in reasonable detail the factors
            constituting such failure and such failure shall not have been cured
            within thirty (30) days after such notice; (ii) any commission of an
            act of fraud, misappropriation, or embezzlement with respect to the
            business or property of the Employer which is intended to result in
            substantial personal enrichment of the Executive or causes material
            harm to the Employer, or (iii) the Executive's conviction of, or
            plea of guilty or NOLO CONTENDERE to, a felony; PROVIDED, HOWEVER,
            the Executive shall not be terminated for Cause unless and until
            there shall have been delivered to the Executive a copy of a
            resolution duly adopted by the affirmative vote of not less than
            three-quarters of the entire membership of the Employer's (or its
            successor's) Board of Directors (the "Board") at a meeting of the
            Board called and held for such purpose, finding that,

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            in the good faith opinion of the Board, the Executive was guilty of
            the alleged conduct and specifying the particulars thereof in
            detail; PROVIDED, FURTHER, that the Executive must have received a
            minimum 30-day notice of such Board meeting and the detailed
            allegations against the Executive, and that the Executive has been
            provided the opportunity, together with the Executive's counsel, to
            be heard before the Board in opposition to the alleged conduct.

       (c)  "Change in Control" shall mean the happening of any one of the
            following events:

            (i)    Upon the acquisition by any person, entity or "group," within
                   the meaning of Section 13(d)(3) or 14(d)(2) of the Securities
                   Exchange Act of 1934 (the "Exchange Act") (other than an
                   acquisition by VGI, the Employer, or any Subsidiary or any
                   employee benefit plan of VGI, the Employer or any Subsidiary)
                   of beneficial ownership (within the meaning of Rule 13d-3
                   promulgated under the Exchange Act) of fifty percent (50%) or
                   more of either the then outstanding shares of common stock of
                   the Employer or VGI, or the combined voting power of either
                   the Employer's or VGI's then outstanding voting securities,
                   entitled to vote generally in the election of directors;

            (ii)   If individuals who constitute the Board of Directors of the
                   Employer or VGI as of the date hereof (each an "Incumbent
                   Board") cease for any reason to constitute at least a
                   majority of such Board of Directors, provided that any person
                   becoming a member of the Board of Directors of either the
                   Employer or VGI subsequent to the date hereof whose election,
                   or nomination for election by the Employer's or VGI's
                   shareholders, was approved by a vote of at least a majority
                   of the directors then comprising the respective Incumbent
                   Board (other than an election or nomination of an individual
                   whose initial assumption of office is in connection with the
                   actual or threatened election contest relating to the
                   election of the directors of the Employer or VGI, as such
                   terms are used in Rule 141-11 of Regulation 14A promulgated
                   under the Exchange act) shall be, for

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                   purposes of this Agreement, considered as though such person
                   were a member of such Incumbent Board; or

            (iii)  Upon approval of the stockholders of the Employer or VGI of
                   (A) a reorganization, merger or consolidation, in each case,
                   with respect to which persons who were shareholders of the
                   Employer or VGI immediately prior to such reorganization,
                   merger or consolidation do not, immediately thereafter, own
                   more than fifty (50%) of the combined voting power entitled
                   to vote generally in the election of directors of the
                   reorganized, merged or consolidated company, (B) a
                   liquidation or dissolution of the Employer or VGI (other than
                   a liquidation or dissolution in connection with a bankruptcy
                   or insolvency or similar event of the Employer or VGI, or a
                   liquidation or dissolution in which shareholders of the
                   Employer or VGI receive less than a total of US $75 million
                   in connection with such liquidation or dissolution), or (C)
                   the sale of all or substantially all of the assets of the
                   Employer or VGI.

       (d)  "Change of Control Benefit" shall have the meaning set forth in
            Section 4.2 hereof.

       (e)  "Retention Benefit" shall have the meaning set forth in Section 4.3
            hereof.

       (f)  "Retention Benefit Payment Period" shall have the meaning set forth
            in Section 4.3 hereof.

       (g)  "Subsidiary" shall mean any person or entity of whom VGI or the
            Employer, directly or indirectly, owns fifty percent (50%) or more
            of the combined voting power entitled to vote generally in the
            election of directors.

       (h)  "Voluntary Termination" shall mean a voluntary termination of
            employment with the Employer by the Executive for reasons other than
            death or disability.

4.2    CHANGE OF CONTROL BENEFIT.

If the Executive is employed with the Employer on the date that a Change of
Control is deemed

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to be effective, the Executive shall be entitled to a cash payment equal to the
Executive's 2001 Compensation (the "Change of Control Benefit"). The Employer
shall pay the Executive the Change of Control Benefit in a lump sum, less
applicable withholdings, within five (5) business days immediately following the
Change of Control. The payment of the Change of Control Benefit shall be in
addition to the payment of all salary and any other amounts otherwise payable to
the Executive under this Agreement, option agreement or other agreements with
the Employer or VGI or otherwise in connection with his employment by the
Employer whether pursuant to employee benefit plans or policies of the Employer
or any severance or other benefit available to the Executive under applicable
law.

4.3    RETENTION BENEFITS.

If the Executive is employed by the Employer or VGI's other Subsidiaries
following a Change of Control, the Executive shall be entitled to accrue a cash
benefit (the "Retention Benefit") provided the Executive remains employed for
one (1) or two (2) 90-day periods immediately following the Change of Control,
(the "Retention Benefit Payment Period"). The accrued quarterly Retention
Benefit shall be an amount equal to the Executive's 2001 Compensation, so that
if the Executive remains employed for the entire Retention Benefit Payment
Period, he would earn a Total Retention Benefit equal to two hundred percent
(200%) of his 2001 Compensation. The Retention Benefit shall be paid to the
Executive in two (2) installments as so earned: The first installment shall be
paid ninety (90) days following the date that a Change of Control is deemed to
be effective, provided that the Executive is so employed by the Employer, VGI or
a Subsidiary on the ninetieth (90th) following a Change of Control, and, if
applicable, a second and final installment shall be paid at the end of the
Retention Benefit Payment Period, provided, that the Executive is so employed as
of the final day of the Retention Benefit Payment Period. If the Executive's
employment with the Employer and VGI and Subsidiaries is terminated following a
Change of Control, but prior to the end of the second 90 day period for any
reason (including death or disability) other than a termination for Cause by the
Employer or a Voluntary Termination, the Employer shall pay the Executive the
full amount of the Retention Benefit that the Executive would have been entitled
to receive from the effective date of the Change of Control through the end of
the Retention Benefit Payment Period. The Employer shall pay such amount to the
Executive within five (5) business days following the termination of

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the Executive's employment. The payment of the Retention Benefit shall be in
addition to the payment of all salary and any other amounts otherwise payable to
the Executive under this Agreement or any option agreement or other agreements
with the Employer or VGI or otherwise in connection with his employment by the
Employer, VGI or one of its Subsidiaries whether pursuant to employee benefit
plans or policies of the Employer, VGI or one of its Subsidiaries, or any
severance or other benefit available to the Executive under applicable law.

4.4    LIMIT ON CHANGE OF CONTROL AND RETENTION BENEFITS.

Notwithstanding any other provision of this Article 4 to the contrary, if any
Retention Benefit payment or payments, or any portion of the Change of Control
Benefit payment, shall be deemed to be a "parachute payment" as defined in
section 280G(b)(2) of the Internal Revenue Code of 1986, as amended (the
"Code"), the Employer shall not be obligated to pay any portion of a Retention
Benefit payment or payments, or any portion of the Change of Control Benefit
payment, to the extent that any such payment or payments shall be deemed an
"excess" parachute payment to the Executive as defined in section 280G(b)(1) of
the Code and not deductible by the Employer in accordance with section 280G(a)
of the Code. Any abatement of payment obligations pursuant to this Section 4.3
shall commence with the last Retention Benefit payment that is earned and
accrued by the Executive pursuant to Section 4.4 hereof, and, if necessary,
shall continue with preceding Retention Benefit payment obligations in the order
of last accrued, first abated, with the Change of Control Benefit payment being
the last payment obligation to be abated, if necessary.

4.5    SUCCESOR LIABILITY.

Any successor to the Employer or VGI (whether directly or indirectly and whether
by purchase, lease, merger, consolidation, or otherwise) or to all or
substantially all of the Employer's or VGI's business and/or assets shall assume
the Employer's or VGI's respective obligations under this Article 4 and agree
expressly to perform the Employer's or VGI's respective obligations under this
Article 4 in the same manner and to the same extent as the Employer or VGI would
be required to perform such obligations in the absence of a succession. For all
purposes under this Article 4, the term "Employer" shall include any successor
to the Employer's business and/or assets and the term "VGI" shall include any
successor to VGI's business and/or assets.

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4.6    TERMINATION UNDER CERTAIN CIRCUMSTANCES.

       (a)  If the Executive's employment terminates for any reason prior to a
            Change in Control, the Executive shall not be entitled to any
            payment of a Change of Control Benefit or any Retention Benefits
            pursuant to this Article 4, but shall be entitled to any payment to
            which the Executive otherwise would be entitled under any other
            provision of this Agreement, under any options agreement or other
            agreements with Employer or VGI to the extent otherwise applicable,
            under the employer's then existing employee benefits plans or
            policies at the time of termination, and under any required
            severance benefits pursuant to applicable law, if any.

       (b)  If, following a Change in Control, the Executive is terminated by
            the Employer for Cause or the Executive has a Voluntary Termination,
            the Executive shall not be entitled to any payment of Retention
            Benefit under this Article 4 for any period following said
            termination, but shall be entitled to any payment to which the
            Executive otherwise would be entitled to under any other provisions
            of this Agreement, under any options agreement or other agreements
            with the Employer or VGI, to the extent otherwise applicable, under
            the Employer's then-existing employee benefit plans or policies at
            the time of termination, and under any required severance benefit
            pursuant to applicable law, if any.

4.7    TERMINATION OF ARTICLE 4.

The Board of the Employer and VGI shall have the right, in their sole
discretion, to terminate the provisions of this Article 4 effective as of
December 31 of any year of the term by delivery of written notice to the
Executive by no later than January 15 of the following year, provided however,
that if a Change of Control occurs prior to such December 31, or if the Employer
or VGI has entered into a binding agreement prior to such December 31 setting
forth the material terms by which the Change of Control will be effected, this
clause shall have no force or effect.

4.8    NO DUTY TO MITIGATE.

The Executive shall not be required to mitigate the amount of any payment
contemplated by this

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Article 4, nor shall any such payment be reduced by any earnings that the
Executive may receive from any other source.

4.9    VGI PRIMARILY OBLIGATED.

VGI shall cause the Employer to perform all of the Employer's obligations under
this Article 4. If the Employer or VGI shall fail to perform, or shall otherwise
be in default of any obligations under this Article 4, the Executive shall have
the right to proceed against the Employer and/or VGI, or both of them, as the
primary obligor under this Article 4 in accordance with the provisions hereof.

4.10   WITHHOLDING.

       All payments made pursuant to this Article 4 shall be subject to
       withholding of applicable income and employment taxes.

5.     CONTRACT PROVISIONS

5.1    GOVERNING LAW.

The validity, interpretation, construction and performance of this Agreement
shall be governed by the internal substantive laws, but not the conflicts of law
rules, of the State of New York.

5.2    Resolution of Disputes.

       (a)  Any dispute or controversy arising out of, relating to, or in
            connection with this Agreement or the interpretation, validity,
            construction, performance, breach, or termination of this Agreement,
            shall be settled by binding arbitration to be held in New York
            County, New York and shall be conducted in accordance with the
            Expedited Employment Arbitration Rules of the American Arbitration
            Association, in effect at the time of the arbitration ("Rules"),
            supplemented, as necessary, by those principles which would be
            applied by a court of law or equity. The arbitrator may grant
            injunctions or other relief in such dispute or controversy. The
            decision of the arbitrator shall be final, conclusive and binding on
            the parties to the arbitration. Judgment may be entered on the
            arbitrator's decision in any court having jurisdiction.

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       (b)  The arbitrator(s) shall apply New York law to the merits of any
            dispute or claim, without reference to conflicts of law rules. The
            arbitration proceedings shall be governed by federal arbitration law
            and by the Rules, without reference to state arbitration law.

       (c)  Notwithstanding anything herein to the contrary, the parties may
            seek specific performance or injunctive relief with respect to the
            matters set forth in this Agreement in the United States District
            Court for the Southern District of New York or a state court located
            in New York County, New York. Each party (i) submits to the
            jurisdiction of any such arbitrator or court for the purpose of any
            such suit, action, or other proceeding, (ii) agrees that such claims
            in respect of any such suit, action or proceeding may be heard and
            determined before any such arbitrator or in any such court, (iii)
            waives, to the fullest extent permitted by law, any immunity it may
            have acquired, or hereafter may acquire, from jurisdiction of any
            such arbitrator or court or from any legal process therein, and (iv)
            agrees not to commence any such suit, action or proceeding other
            than before such arbitrator or in such court, and waives, to the
            fullest extent permitted by applicable law, any claim that any such
            suit, action or proceeding is brought in an inconvenient forum. Each
            party hereby irrevocably designates CT Corporation System, 111
            Eighth Avenue, New York, New York 10011 as agent upon whom process
            against it may be served for the purposes of this Agreement.

       (d)  EXECUTIVE HAS READ AND UNDERSTANDS THIS SECTION 5.2, WHICH DISCUSSES
            ARBITRATION. EXECUTIVE UNDERSTANDS THAT SUBMITTING ANY CLAIMS
            ARISING OUT OF, RELATING TO, OR IN CONNECTION WITH THIS AGREEMENT,
            OR THE INTERPRETATION, VALIDITY, CONSTRUCTION, PERFORMANCE, BREACH
            OR TERMINATION THEREOF TO BINDING ARBITRATION, CONSTITUTES A WAIVER
            OF EXECUTIVES RIGHT TO A JURY TRIAL AND RELATES TO THE RESOLUTION OF
            ALL DISPUTES RELATING TO AND ARISING FROM THIS AGREEMENT.

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5.3    HEADINGS.

The headings of the Sections herein are inserted for convenience of reference
only and shall not affect the meaning or construction hereof.

5.4    WITHHOLDING.

All payment under this Agreement shall be subject to withholding of such
amounts, if any, relating to tax or other payroll deductions as the Employer may
reasonably determine and should withhold pursuant to any applicable law or
regulation.

5.5    COUNTERPARTS.

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

5.6    WAIVER.

The failure of any party to enforce its rights under this Agreement at any time
for any period shall not be construed as a waiver of such rights and a waiver
shall only be construed as such if made in writing signed by a duly authorized
representative of the waiving party.

5.7    SEVERABILITY.

If any provision of this Agreement or application of any such provision to any
person or circumstances shall be invalid under the law of any jurisdiction the
remainder of this Agreement or the application of such provision to persons or
circumstances other than those as to which it is invalid shall not be effected
thereby. In the event a court of competent jurisdiction rules any provision of
this Agreement to be invalid, then such ruling shall have no effect on the
remaining provisions of this Agreement and they shall continue in full force and
effect.

5.8    ENTIRE AGREEMENT.

This Agreement, contains the entire contract of Employment between the parties
hereto with respect to the subject matter of this Agreement, and supersedes and
replaces all previous negotiations, understandings and agreements whether verbal
or written with respect to any matters herein referred to. The parties
acknowledge that the provisions of the Confidentiality and

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Invention Assignment Agreement dated December 14, 1999 between Employer and the
Executive remains in full force and effect.

5.9    SURVIVAL.

The provisions of Articles hereof shall survive the termination of this
Agreement for the periods of time specified or contemplated therein.

5.10   DIRECTORS AND OFFICERS.

If the Executive is a director or officer at the relevant time, the Executive
agrees that after termination of his employment with the Employer for any
reason, he will, on the date of his termination, tender his resignation from any
position he may hold as an officer or director of the Employer or any of its
affiliated or associated companies.

5.11   NOTICES.

Notices and all other communications contemplated by this Agreement shall be in
writing and shall be deemed to have been duly given when personally delivered by
either FedEx of other reputable overnight courier service or by registered or
certified U.S. mail, return receipt requested. In the case of the Executive,
mailed notices shall be addressed to him at the home address which he most
recently communicated to the Employer in writing. In the case of the Employer,
mailed notices shall be addressed to its corporate headquarters, and all notices
shall be directed to the attention of its President, with a copy to Visible
Genetics Inc., 700 Bay Street, Toronto, Ontario, M5G ZG Canada, attention:
General Counsel. All notices to VGI shall be delivered to the foregoing address.
Notices shall be deemed deliverable and received upon receipt or refusal of
receipt.

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            IN WITNESS WHEREOF this Agreement is executed as of the day, month
and year first above written.

                                      )   VISIBLE GENETICS INC.
                                      )
                                         ---------------------------------------
                                      )   Per:
                                      )
                                      )
                                         ---------------------------------------
                                      )   Per:
                                      )
                                      )
                                      )
                                      )   VISIBLE GENETICS CORPORATION


                                         ---------------------------------------
                                          Per:

                                         ---------------------------------------
                                          Per:

                                         ---------------------------------------
                                          Thomas J. Clarke

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