EXHIBIT 99.1

                               FORM OF PROXY CARD
                              DIANON SYSTEMS, INC.
                                      PROXY

      THE UNDERSIGNED HEREBY APPOINTS KEVIN C. JOHNSON AND DAVID R. SCHREIBER,
AND EACH OF THEM, AS PROXIES, EACH WITH THE POWER TO APPOINT THEIR SUBSTITUTE,
AND HEREBY AUTHORIZES THEM TO REPRESENT AND TO VOTE AS DESIGNATED BELOW ALL THE
SHARES OF COMMON STOCK OF DIANON SYSTEMS, INC. (THE "COMPANY") HELD OF RECORD BY
THE UNDERSIGNED ON AUGUST 29, 2001 AT THE ANNUAL MEETING OF STOCKHOLDERS TO BE
HELD AT THE COMPANY'S CORPORATE HEADQUARTERS AT 200 WATSON BOULEVARD, STRATFORD,
CONNECTICUT, ON OCTOBER 1, 2001 AT 10:00 A.M., AND AT ANY ADJOURNMENT THEREOF.

Change of Address

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PLEASE MARK YOUR VOTES AS INDICATED IN THIS EXAMPLE [X]

PLEASE VOTE BY RETURNING THE ATTACHED PROXY CARD

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE FOR ALL OF THE NOMINEES
LISTED IN PROPOSAL (1) AND FOR PROPOSALS (2), (3) AND (4).

1. Election of the following nominees for Director: Kevin C. Johnson, John P.
   Davis, Bruce K. Crowther, E. Timothy Geary, G. S. Beckwith Gilbert, David R.
   Schreiber, Jeffrey L. Sklar and James T. Barry.

        FOR All NOMINEES LISTED     WITHHOLD AUTHORITY TO VOTE FOR
                 ABOVE                ALL NOMINEES LISTED ABOVE
                  [ ]                             [ ]

   To withhold your vote for any individual nominee, write the name on the line
below.

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2. Proposal to approve of the issuance of the shares of Dianon Common Stock to
   be issued pursuant to the Agreement and Plan of Merger, dated as of June 28,
   2001, among Dianon Systems, Inc., UroCor Acquisition Corp. and UroCor, Inc.

               FOR              AGAINST           ABSTAIN
               [ ]                [ ]               [ ]

3. Proposal to approve the adoption of the 2001 Stock Incentive Plan.

               FOR              AGAINST           ABSTAIN
               [ ]                [ ]               [ ]

4. Proposal to ratify the appointment of Arthur Andersen, LLP as independent
   public accountants for the year ending December 31, 2001.

               FOR              AGAINST           ABSTAIN
               [ ]                [ ]               [ ]




[ ]   CHECK IF YOU PLAN TO ATTEND THE ANNUAL MEETING IN PERSON.

Vote, sign and date this Proxy and return it promptly in the enclosed envelope.
No postage is required if mailed in the United States.

[ ]   CHANGE OF ADDRESS ON REVERSE SIDE





THIS PROXY, WHEN PROPERLY EXECUTED, WILL BE VOTED AS DIRECTED OR IF NO CONTRARY
DIRECTION IS INDICATED WILL BE VOTED AS MANAGEMENT RECOMMENDS ON THESE AND ANY
OTHER MATTERS THAT MAY PROPERLY COME BEFORE THE MEETING OR ANY ADJOURNMENT(S) OR
POSTPONEMENT(S) THEREOF. PLEASE SIGN THIS PROXY AND RETURN IT PROMPTLY IN THE
ENVELOPE PROVIDED.

Signature __________________________________    Dated_______________

NOTE: Please sign exactly as name appears hereon. Joint owners should each sign.
When signing as attorney, executor, administrator, trustee or guardian, please
give full title as such.

      If time warrants, improperly signed cards will be returned for correction.

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