SECURITIES AND EXCHANGE COMMISSION
                           Washington, D.C. 20549


                                SCHEDULE 13D
                               (Rule 13d-101)

          INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
         TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO
                               RULE 13d-2(a)
                           (Amendment No. ____ )*

                                Vysis, Inc.

                              (Name of Issuer)

                  Common Stock, par value $.001 per share

                       (Title of Class of Securities)

                                928961-10-1

                               (CUSIP Number)

                              Jose M. de Lasa
                            100 Abbott Park Road
                      Abbott Park, Illinois 60064-6049
                           Phone: (847) 937-8905

          (Name, Address and Telephone Number of Person Authorized
                   to Receive Notices and Communications)

                                  Copy to:
                       Charles W. Mulaney, Jr., Esq.
                    Skadden, Arps, Slate, Meagher & Flom
                           333 West Wacker Drive
                          Chicago, Illinois 60606
                         Telephone: (312) 407-0700

                              October 24, 2001

          (Date of Event Which Requires Filing of This Statement)

         If the filing person has previously filed a statement on Schedule
13G to report the acquisition that is the subject of this Schedule 13D, and
is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g),
check the following box. |_|

         Note: Schedules filed in paper format shall include a signed
original and five copies of the schedule, including all exhibits. See Rule
13d-7 for other parties to whom copies are sent.

                       (Continued on following pages)

                            (Page 1 of 13 Pages)
--------------

         *The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect to the subject
class of securities, and for any subsequent amendment containing
information which would alter disclosures provided in a prior cover page.

         The information required on the remainder of this cover page shall
not be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934, as amended (the "Act") or otherwise subject to the
liabilities of that section of the Act but shall be subject to all other
provisions of the Act (however, see the Notes).


--------------------------------------------------------------------------------

CUSIP No. 928961-10-1             13D                Page  2  of  13 Pages
--------------------------------------------------------------------------------

     1        NAME OF REPORTING PERSON
              I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
              ABBOTT LABORATORIES (I.R.S. IDENTIFICATION NO. 36-0698440)
--------------------------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP          (a) |_|
                                                                        (b) |_|
--------------------------------------------------------------------------------
     3        SEC USE ONLY

--------------------------------------------------------------------------------
     4        SOURCE OF FUNDS
              OO
--------------------------------------------------------------------------------
     5        CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS          |_|
              REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
--------------------------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              ILLINOIS
--------------------------------------------------------------------------------

 NUMBER OF                      7      SOLE VOTING POWER
  SHARES
BENEFICIALLY                           -0-
 OWNED BY                  -----------------------------------------------------
   EACH                         8      SHARED VOTING POWER
 REPORTING
  PERSON                               6,662,682
   WITH                    -----------------------------------------------------
                                9      SOLE DISPOSITIVE POWER

                                       -0-
                           ----------------------------------------------------
                               10      SHARED DISPOSITIVE POWER
                                       6,662,682
--------------------------------------------------------------------------------
    11        AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              6,662,682
--------------------------------------------------------------------------------
    12        CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
              CERTAIN SHARES          |_|

--------------------------------------------------------------------------------
    13        PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

              64.7%*
--------------------------------------------------------------------------------
    14        TYPE OF REPORTING PERSON
              CO
--------------------------------------------------------------------------------

*   The calculation of the foregoing percentage is based on the number of
    shares of Vysis common stock disclosed by Vysis in its
    Solicitation/Recommendation Statement on Schedule 14D-9 dated October
    31, 2001.



--------------------------------------------------------------------------------

CUSIP No. 928961-10-1                    13D           Page  3  of  13 Pages
--------------------------------------------------------------------------------
     1        NAME OF REPORTING PERSON
              I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
              RAINBOW ACQUISITION CORP.
--------------------------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP         (a) |_|
                                                                       (b) |_|
--------------------------------------------------------------------------------
     3        SEC USE ONLY

--------------------------------------------------------------------------------
     4        SOURCE OF FUNDS
              OO
--------------------------------------------------------------------------------
     5        CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS          |_|
              REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)
--------------------------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              DELAWARE
--------------------------------------------------------------------------------
 NUMBER OF                      7      SOLE VOTING POWER
  SHARES
BENEFICIALLY                           -0-
 OWNED BY                       ------------------------------------------------
   EACH                         8      SHARED VOTING POWER
 REPORTING
  PERSON                              6,662,682
   WITH                         ------------------------------------------------
                                9      SOLE DISPOSITIVE POWER

                                      -0-
                                ------------------------------------------------
                                10     SHARED DISPOSITIVE POWER
                                       6,662,682
--------------------------------------------------------------------------------
    11        AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              6,662,682
--------------------------------------------------------------------------------
    12        CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
              SHARES     |_|

--------------------------------------------------------------------------------
    13        PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

              64.7%*
--------------------------------------------------------------------------------

    14        TYPE OF REPORTING PERSON
              CO
--------------------------------------------------------------------------------

*   The calculation of the foregoing percentage is based on the number of
    shares of Vysis common stock disclosed by Vysis in its
    Solicitation/Recommendation Statement on Schedule 14D-9 dated October
    31, 2001.


Item 1.  Security and Issuer.

         This statement relates to shares of the common stock, par value
$.001 per share (the "Shares"), of Vysis, Inc., a Delaware corporation
("Vysis"), whose principal executive offices are located at 3100 Woodcreek
Drive, Downers Grove, Illinois, 60515-5400.

Item 2.  Identity and Background.

         The persons filing this statement are Abbott Laboratories
("Abbott"), an Illinois corporation, for and on behalf of itself and
Rainbow Acquisition Corp. ("Merger Sub"), a Delaware corporation and a
wholly-owned subsidiary of Abbott.

         Abbott's principal business is the discovery, development,
manufacture, and sale of a broad and diversified line of health care
products and services. Abbott is an Illinois corporation with its principal
office located at 100 Abbott Park Road, Abbott Park, Illinois 60064-6049.
The telephone number of Abbott is (847) 937-6100.

         Merger Sub is a Delaware corporation with its principal office
located at 100 Abbott Park Road, Abbott Park, Illinois 60064-6049. The
telephone number of Merger Sub is (847) 937-6100. Merger Sub was
incorporated on October 17, 2001, for the purpose of making a tender offer
for all of the Shares and has engaged in no business other than in
connection with the transactions contemplated by the Merger Agreement and
the Stockholder Agreement (as defined below).

         The names, citizenship, business addresses, present principal
occupation or employment, and the name and principal business and address
of any corporation or other organization in which such employment is
conducted, of the directors and executive officers of Abbott and Merger Sub
are as set forth in Annex 1 hereto and incorporated herein by this
reference.

         Neither Abbott, Merger Sub, nor, to their knowledge, any person
listed in Annex 1 has during the last five years (i) been convicted in a
criminal proceeding (excluding traffic violations or similar misdemeanors)
or (ii) been a party to a civil proceeding of a judicial or administrative
body of competent jurisdiction and as a result of such proceeding was or is
subject to a judgment, decree or final order enjoining future violations
of, or prohibiting or mandating activities subject to, federal or state
securities laws or finding any violation with respect to such laws.

Item 3.  Source and Amount of Funds or Other Consideration.

         Merger Sub intends to purchase all of the Shares in the Offer (as
defined below). The Offer is not conditioned upon Abbott's or Merger Sub's
ability to finance the purchase of Shares pursuant to the Offer. Abbott and
Merger Sub estimate that the total amount of funds required to purchase all
of the outstanding Shares pursuant to the Offer and the Merger will be
approximately $355 million, net of Vysis' anticipated cash balances, plus
approximately $7 million in related fees and expenses for Abbott and Vysis.
Abbott has available to it sufficient funds to close the Offer and the
Merger, and will cause Merger Sub to have sufficient funds available to
close the Offer and the Merger. Abbott intends to obtain the necessary
funds from the issuance of its commercial paper in the ordinary course. In
the event that such financings are unavailable, Abbott will arrange
alternate financing.

Item 4.  Purpose of Transaction.

         Abbott, Merger Sub, BP America Inc., a Delaware corporation ("BP")
and Amoco Technology Company, a Delaware corporation and wholly owned
subsidiary of BP ("ATC") entered into a Stockholder Agreement (the
"Stockholder Agreement"), dated as of October 24, 2001, as a condition of
and an inducement to Abbott's and Merger Sub's willingness to enter into an
Agreement and Plan of Merger (the "Merger Agreement"), dated as of October
24, 2001, by and among Abbott, Merger Sub and Vysis, by means of which
Abbott would acquire 100% of the equity of Vysis.

         Pursuant to the Merger Agreement, Merger Sub is offering to
purchase all outstanding Shares at a price of $30.50 per Share, net to the
seller in cash, upon the terms and subject to the conditions set forth in
the Offer to Purchase and in the related Letter of Transmittal (which,
together with any amendments or supplements thereto, collectively
constitute the "Offer") filed by Abbott with the Securities and Exchange
Commission on October 31, 2001 as exhibits to a Tender Offer Statement on
Schedule TO (the "Schedule TO").

         The Offer is being made pursuant to the Merger Agreement. The
Merger Agreement provides, among other things, that, subject to certain
conditions, Merger Sub will be merged with and into Vysis (the "Merger")
with Vysis continuing as the surviving corporation, wholly owned by Abbott.
Pursuant to the Merger Agreement, at the effective time of the Merger (the
"Effective Time"), each Share outstanding immediately prior to the
Effective Time (other than Shares held by Vysis as treasury stock, or owned
by any subsidiaries of Vysis, Abbott, Merger Sub or any of Abbott's other
subsidiaries, all of which will be cancelled and retired and shall cease to
exist, and other than Shares that are held by stockholders, if any, who
properly exercise their dissenters' rights under the Delaware General
Corporation Law), will be converted into the right to receive $30.50 or any
greater per Share price paid in the Offer in cash.

         The Offer is conditioned upon, among other things, (i) there being
validly tendered in accordance with the terms of the Offer and not
withdrawn prior to the expiration date of the Offer that number of Shares
that, together with the Shares then beneficially owned by Abbott or Merger
Sub, represents at least 51% of the then outstanding Shares on a fully
diluted basis and (ii) the expiration or termination of the waiting periods
under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended,
and the regulations thereunder, and the pre-merger notification
requirements of Germany. The Offer is also subject to the satisfaction of
certain other conditions described more fully in the Offer to Purchase, a
copy of which was filed as Exhibit (a)(1)(A) to the Schedule TO and which
is incorporated by this reference in this Item 4 in its entirety.

         Concurrently with the execution of the Merger Agreement, Abbott
and Merger Sub entered into the Stockholder Agreement. Capitalized terms
not defined in this Item 4 shall have the meaning given to them in the
Stockholder Agreement. ATC has represented that it owns 6,662,682 Shares.
As of October 24, 2001, ATC's Shares represented 64.7% of the outstanding
Shares. Pursuant to the Stockholder Agreement, ATC has agreed to tender all
its Shares into the Offer no later than the fifth (5th) business day
following commencement of the Offer. ATC has also agreed to (i) vote its
Shares in favor of the Merger, (ii) vote its Shares against any action that
would result in any of Vysis's obligations under the Merger Agreement not
being fulfilled and (iii) vote its Shares against any action that would
delay, postpone or attempt to discourage the Merger or the Offer or cause a
condition to the closing of the Merger or the Offer not to be satisfied.

         Pursuant to the Stockholder Agreement, ATC also agreed that, until
the earlier of the Effective Time or the termination of the Stockholder
Agreement, it will not (and will not permit any of its affiliates,
officers, directors or employees or any investment banker, financial
advisor, attorney, accountant or other representative retained by it or any
affiliate (collectively "Stockholder Representatives") to), directly or
indirectly: (i) solicit, initiate, engage in discussions or negotiate with
any Person or take any other action intended or designed to facilitate any
inquiry or effort of any Person (other than Abbott) relating to any direct
or indirect acquisition of all or a substantial part of the business and
properties of Vysis or any of the subsidiaries of Vysis or any capital
stock of Vysis or any of the subsidiaries of Vysis, whether by merger,
tender offer, exchange offer, sale of assets or similar transactions
involving Vysis or any of its subsidiaries, divisions or operating or
principal business units ("Alternative Acquisition"); (ii) provide
information with respect to Vysis or any subsidiary of Vysis to any Person
(other than Abbott) relating to a possible Alternative Acquisition by any
Person (other than Abbott) or (iii) enter into any agreement with respect
to any proposal for an Alternative Acquisition ("Alternative Acquisition
Proposal"). Prior to the acceptance for payment of Shares pursuant to the
Offer, ATC may advise the board of directors of Vysis of receipt by it (or
any Stockholder Representative) of any unsolicited Alternative Acquisition
Proposal or any inquiry indicating that any Person is considering making or
wishes to make an Alternative Acquisition Proposal.

         The Stockholder Agreement requires that ATC and BP cease and cause
to be terminated immediately all existing discussions or negotiations
conducted by them or at their behest, prior to the date of the Stockholder
Agreement, with respect to any Alternative Acquisition. In addition, the
Stockholder Agreement requires BP to promptly direct UBS Warburg LLC
("UBS") to cease and cause to be terminated immediately all discussions or
negotiations conducted by it, prior to the date of the Stockholder
Agreement, with respect to any Alternative Acquisition, on behalf of BP or
its affiliates.

         Pursuant to the Stockholder Agreement, ATC has agreed to defend,
indemnify and hold harmless Abbott, Merger Sub, Vysis, each subsidiary of
Vysis and their respective officers, directors and affiliates for: (i) any
and all taxes of BP and any current or former affiliate of BP (other than
Vysis or any subsidiary of Vysis) for any taxable period beginning before
the closing date of the Merger, for which Vysis or any subsidiary of Vysis
may be liable as part of the same consolidated or affiliated group pursuant
to Treasury Regulation Sec. 1.1502-6 (or any similar provision of state,
local or foreign law), as a transferee or successor, by contract, agreement
or otherwise; (ii) any and all taxes imposed on or with respect to Vysis or
any subsidiary of Vysis for any taxable period (or portion thereof) ending
on or before February 10, 1998 and (iii) any and all expenses arising from
any indemnified taxes. BP has agreed to guarantee these indemnification
obligations of ATC.

         The Stockholder Agreement requires that BP pay any fees, expenses
or other amounts that become due and payable by Vysis to UBS or any other
investment bank or financial advisor engaged by Vysis other than Wachovia
Securities (a tradename of First Union Securities, Inc.) and Goldman, Sachs
& Co. as a result of the transactions. BP must also defend, indemnify and
hold harmless Abbott, Merger Sub, Vysis, each subsidiary of Vysis and their
respective officers, directors and affiliates against any claims for such
amounts or any liabilities or costs arising out of or resulting from any
claims for such amounts.

         The Stockholder Agreement terminates upon the earlier of (i) the
termination of the Offer without the purchase of Shares thereunder, (ii)
the termination of the Merger Agreement in accordance with its terms or
(iii) the consummation of the Merger; provided that the indemnification
provisions described above shall survive the consummation of the Merger.

         Pursuant to the terms of the Merger Agreement, promptly upon the
purchase of and payment for any Shares by the Merger Sub pursuant to the
Offer, Abbott currently intends to seek maximum representation on the board
of directors of Vysis, subject to the requirement in the Merger Agreement
regarding the presence of at least three (3) Independent Directors on the
Vysis board until the Effective Time. The directors of Merger Sub
immediately prior to the Effective Time will become the directors of Vysis
upon consummation of the Merger in accordance with the terms of the Merger
Agreement. In addition, the Merger Agreement provides that the certificate
of incorporation and by-laws of Merger Sub immediately prior to the
Effective Time will become the certificate of incorporation and by-laws of
Vysis after the consummation of the Merger.

         Abbott anticipates that, if the Merger is completed in accordance
with the Merger Agreement, Vysis will become a wholly-owned subsidiary of
Abbott, that Abbott will seek to cause the Shares to be delisted from
quotation on the Nasdaq National Market and that the Shares would become
eligible for termination of registration pursuant to Section 12(g)(4) of
the Securities Exchange Act of 1934, as amended.

         Other than as described in this Item 4, Abbott and Merger Sub have
no plans or proposals which would relate to or result in any of the matters
listed in paragraphs (a) through (j) of Item 4 of Schedule 13D (although
Abbott and Merger Sub reserve the right to formulate specific plans and
proposals with respect to, or change their intentions regarding, any or all
of the foregoing, subject to the terms of the Merger Agreement and the
Stockholder Agreement).

         The information set forth, or incorporated by reference, in Items
3, 5 and 6 of this statement is hereby incorporated by this reference in
this Item 4.

         References to, and descriptions of, the Merger Agreement and the
Stockholder Agreement in this Item 4 are qualified in their entirety by
this reference to the Merger Agreement and the Stockholder Agreement,
copies of which were filed as Exhibits (d)(1) and (d)(2), respectively, to
the Schedule TO and which are incorporated by this reference in this Item 4
in their entirety where such references and descriptions appear.

Item 5.  Interest in Securities of the Issuer.

         (a) and (b) For the purpose of Rule 13d-3 promulgated under the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), Merger
Sub and Abbott, by reason of the execution and delivery of the Stockholder
Agreement, may be deemed to have shared voting power and/or shared
dispositive power with respect to (and therefore beneficially own)
6,662,682 Shares, representing 64.7% of the Shares. Except as set forth in
this Item 5, none of Merger Sub, Abbott or, to their knowledge, any person
listed in Annex 1 hereto, owns beneficially any Shares.

         Neither Merger Sub nor Abbott have the sole power to vote or to
direct the vote of any Shares. Neither Merger Sub nor Abbott have the sole
power to dispose or to direct the disposition of any Shares.

         Each of Abbott and Merger Sub expressly disclaims beneficial
ownership of the Shares owned by ATC.

         (c) Except for the execution and delivery of the Stockholder
Agreement and the Merger Agreement, no transactions in the Shares were
effected by Merger Sub, Abbott or, to their knowledge, any person listed in
Annex 1 hereto, during the 60 days prior to the date hereof.

         (d) Inapplicable.

         (e) Inapplicable.

         References to, and descriptions of, the Merger Agreement and the
Stockholder Agreement in this Item 5 are qualified in their entirety by
this reference to the Merger Agreement and the Stockholder Agreement,
copies of which were filed as Exhibits (d)(1) and (d)(2), respectively, to
the Schedule TO and which are incorporated by this reference in this Item 5
in their entirety where such references and descriptions appear.

Item 6. Contracts, Arrangements, Understandings or Relationships With
        Respect to Securities of the Issuer.

         The information set forth, or incorporated by reference, in Items
3 through 5 of this statement is hereby incorporated by this reference. To
Abbott's and Merger Sub's knowledge, except as otherwise described in this
Schedule 13D, there are no contracts, arrangements, understandings or
relationships among the persons named in Item 2 above, and between any such
persons and any other person, with respect to any securities of Vysis.

Item 7.  Material to be Filed as Exhibits.


    Exhibit                         Description

       1          Agreement and Plan of Merger, dated as of October 24,
                  2001, by and among Abbott Laboratories, Rainbow
                  Acquisition Corp., and Vysis, Inc. (incorporated herein
                  by reference to Exhibit (d)(1) to the Schedule TO)

       2          Stockholder Agreement, dated as of October 24, 2001, by
                  and among Abbott Laboratories, Rainbow Acquisition Corp.,
                  Amoco Technology Company and BP America Inc.
                  (incorporated herein by reference to Exhibit (d)(2) to
                  the Schedule TO)

       3          Offer to Purchase dated October 31, 2001 (incorporated
                  herein by reference to Exhibit (a)(1)(A) to the Schedule
                  TO)

       4          Joint Filing Agreement, dated November 1, 2001, between
                  Abbott Laboratories and Rainbow Acquisition Corp.



                                 SIGNATURE

         After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement is true,
complete and correct.


Dated:  November 1, 2001

                                 ABBOTT LABORATORIES


                                 By:      /s/ RICHAED A. GONZALEZ
                                          ---------------------------
                                          Name:  Richard A. Gonzalez
                                          Title:  Executive Vice President,
                                                  Medical Products


                                 RAINBOW ACQUISITION CORP.


                                 By:      /s/ THOMAS C. FREYMAN
                                          --------------------------
                                          Name:  Thomas C. Freyman
                                          Title:   Vice-President

                                                                        Annex 1


               Information Concerning Executive Officers and
                      Directors of Abbott Laboratories



         The current corporate officers and directors of Abbott
Laboratories are listed below. The current business address of each person
is 100 Abbott Park Road, Abbott Park, Illinois 60064-6400 and the current
phone number is (847) 937-6100. Unless otherwise indicated, all positions
set forth below opposite an individual's name refer to positions within
Abbott Laboratories. Abbott Laboratories does not consider all of its
corporate officers to be executive officers as defined by the Securities
Exchange Act of 1934 or Releases thereunder.


------------------------------------------------------------------------------------------------------------- NAME POSITION/PRESENT PRINCIPAL OCCUPATION CITIZENSHIP OR EMPLOYMENT AND BUSINESS ADDRESS ------------------------------------------------------------------------------------------------------------- CORPORATE OFFICERS ------------------------------------------------------------------------------------------------------------- Miles D. White(1) Chairman of the Board and Chief Executive Officer U.S.A. ------------------------------------------------------------------------------------------------------------- Jeffrey M. Leiden(1) Executive Vice President, Pharmaceuticals and Chief U.S.A. Scientific Officer, and Director ------------------------------------------------------------------------------------------------------------- Richard A. Gonzalez(1) Executive Vice President, Medical Products U.S.A. ------------------------------------------------------------------------------------------------------------- Christopher B. Begley(1) Senior Vice President, Hospital Products U.S.A. ------------------------------------------------------------------------------------------------------------- Thomas D. Brown(1) Senior Vice President, Diagnostic Operations U.S.A. ------------------------------------------------------------------------------------------------------------- Jose M. de Lasa(1) Senior Vice President, Secretary and General Counsel U.S.A. ------------------------------------------------------------------------------------------------------------- William G. Dempsey(1) Senior Vice President, International Operations U.S.A. ------------------------------------------------------------------------------------------------------------- Gary L. Flynn(1) Senior Vice President, Ross Products U.S.A. ------------------------------------------------------------------------------------------------------------- Thomas C. Freyman(1) Senior Vice President, Finance and Chief Financial Officer U.S.A. ------------------------------------------------------------------------------------------------------------- David B. Goffredo(1) Senior Vice President, Pharmaceutical Operations U.S.A. ------------------------------------------------------------------------------------------------------------- Greg W. Linder(1) Vice President and Controller U.S.A. ------------------------------------------------------------------------------------------------------------- Thomas M. Wascoe(1) Senior Vice President, Human Resources U.S.A. ------------------------------------------------------------------------------------------------------------- Lance B. Wyatt(1) Senior Vice President, Specialty Products U.S.A. ------------------------------------------------------------------------------------------------------------- Catherine V. Babington Vice President, Investor Relations and Public Affairs U.S.A. ------------------------------------------------------------------------------------------------------------- Patrick J. Balthrop Vice President, Vascular Devices U.S.A. ------------------------------------------------------------------------------------------------------------- Mark E. Barmak Vice President, Government Affairs U.S.A. ------------------------------------------------------------------------------------------------------------- Michael G. Beatrice Vice President, Corporate Regulatory and Quality Science U.S.A. ------------------------------------------------------------------------------------------------------------- Christopher A. Bleck Vice President, Pediatrics, Ross Products U.S.A. ------------------------------------------------------------------------------------------------------------- Douglas C. Bryant Vice President, Diagnostic Operations, Asia and Pacific U.S.A. ------------------------------------------------------------------------------------------------------------- Gary R. Byers Vice President, Internal Audit U.S.A. ------------------------------------------------------------------------------------------------------------- Thomas F. Chen Vice President, Pacific, Asia, and Africa Operations U.S.A. ------------------------------------------------------------------------------------------------------------- Michael J. Collins Vice President, Diagnostic Operations, U.S. U.S.A. ------------------------------------------------------------------------------------------------------------- Edward J. Fiorentino Vice President, MediSense Products U.S.A. ------------------------------------------------------------------------------------------------------------- Stephen R. Fussell Vice President, Compensation and Development U.S.A. ------------------------------------------------------------------------------------------------------------- Robert B. Hance Vice President, Diagnostic Operations, Europe, Africa and U.S.A. Middle East ------------------------------------------------------------------------------------------------------------- Guillermo A. Herrera Vice President, European Operations U.S.A. ------------------------------------------------------------------------------------------------------------- Terrence C. Kearney Vice President and Treasurer U.S.A. ------------------------------------------------------------------------------------------------------------- James J. Koziarz, Ph.D. Vice President, Diagnostic Products Research and Development U.S.A. ------------------------------------------------------------------------------------------------------------- John C. Landgraf Vice President, Corporate Engineering U.S.A. ------------------------------------------------------------------------------------------------------------- Elaine R. Leavenworth Vice President, Washington Government Affairs U.S.A. ------------------------------------------------------------------------------------------------------------- John M. Leonard Vice President, Global Pharmaceutical Drug Development U.S.A. ------------------------------------------------------------------------------------------------------------- Holger Liepmann Vice President, Japan Operations Germany ------------------------------------------------------------------------------------------------------------- John F. Lussen Vice President, Taxes U.S.A. ------------------------------------------------------------------------------------------------------------- P. Loreen Mershimer Vice President, Hospital Products Business Sector U.S.A. ------------------------------------------------------------------------------------------------------------- Edward L. Michael Vice President, Diagnostic Assays and Systems U.S.A. ------------------------------------------------------------------------------------------------------------- Karen L. Miller Vice President, Information Technology U.S.A. ------------------------------------------------------------------------------------------------------------- Daniel W. Norbeck Vice President, Global Pharmaceutical Discovery U.S.A. ------------------------------------------------------------------------------------------------------------- Edward A. Ogunro Vice President, Hospital Products Research and Development, U.S.A. Medical and Regulatory Affairs ------------------------------------------------------------------------------------------------------------- Roberto Reyes Vice President, Latin America and Canada Columbia ------------------------------------------------------------------------------------------------------------- Mary T. Szela Vice President, Hospital Products Business Sector U.S.A. ------------------------------------------------------------------------------------------------------------- Marcia A. Thomas Vice President, Diagnostic Quality Assurance, Regulatory U.S.A. Affairs and Compliance ------------------------------------------------------------------------------------------------------------- James L. Tyree Vice President, Global Licensing/New Business Developmen U.S.A. ------------------------------------------------------------------------------------------------------------- Steven J. Weger Vice President, Corporate Planning and Development U.S.A. ------------------------------------------------------------------------------------------------------------- Susan M. Widner Vice President, Abbott Health Systems U.S.A. ------------------------------------------------------------------------------------------------------------- DIRECTORS ------------------------------------------------------------------------------------------------------------- Roxanne S. Austin President and Chief Operating Officer, DIRECTV, Inc. U.S.A. ------------------------------------------------------------------------------------------------------------- H. Laurance Fuller Co-Chairman, BP Amoco, p.l.c. (Retired) U.S.A ------------------------------------------------------------------------------------------------------------- Jack M. Greenberg Chairman and Chief Executive Officer, McDonald's Corporation U.S.A. ------------------------------------------------------------------------------------------------------------- David A. Jones Chairman, Humana Inc. U.S.A. ------------------------------------------------------------------------------------------------------------- Jeffrey M. Leiden Officer of Abbott U.S.A. ------------------------------------------------------------------------------------------------------------- The Rt. Hon. Lord Owen Physician, Politician, and Businessman U.K. CH ------------------------------------------------------------------------------------------------------------- Boone Powell, Jr. Chairman, Baylor Health Care System (Retired) U.S.A. ------------------------------------------------------------------------------------------------------------- Addison Barry Rand Chairman and Chief Executive Officer, Avis Group Holdings, Inc. (Retired) U.S.A. ------------------------------------------------------------------------------------------------------------- Dr. W. Ann Reynolds President, The University of Alabama at Birmingham U.S.A. ------------------------------------------------------------------------------------------------------------- Roy S. Roberts Group Vice President, North American Vehicle Sales, Service U.S.A. and Marketing, General Motors Corporation (Retired) ------------------------------------------------------------------------------------------------------------- William D. Smithburg Chairman, President and Chief Executive Officer, The Quaker U.S.A. Oats Company (Retired) ------------------------------------------------------------------------------------------------------------- John R. Walter Chairman, Ashlin Management Corp. U.S.A. ------------------------------------------------------------------------------------------------------------- Miles D. White Officer of Abbott U.S.A. -------------------------------------------------------------------------------------------------------------
-------- (1) Pursuant to Item 401 (b) of Regulation S-K Abbott has identified these persons as "executive officers" within the meaning of Item 401 (b). Information Concerning Executive Officers and Directors of Rainbow Acquisition Corp. The current corporate officers and directors of Rainbow Acquisition Corp. are listed below. The current business address of each person is 100 Abbott Park Road, Abbott Park, Illinois 60064-6400 and the current phone number is (847) 937-6100. All positions set forth below opposite an individual's name refer to positions within Rainbow Acquisition Corp.
-------------------------------------------------------------------------------------------------------------------- NAME POSITION/PRESENT PRINCIPAL OCCUPATION OR EMPLOYMENT AND CITIZENSHIP BUSINESS ADDRESS -------------------------------------------------------------------------------------------------------------------- CORPORATE OFFICERS AND DIRECTORS -------------------------------------------------------------------------------------------------------------------- Thomas C. Freyman Vice President and Director U.S.A. -------------------------------------------------------------------------------------------------------------------- Thomas D. Brown President U.S.A. -------------------------------------------------------------------------------------------------------------------- Honey Lynn Goldberg Secretary U.S.A. -------------------------------------------------------------------------------------------------------------------- Terrence C. Kearney Treasurer U.S.A. -------------------------------------------------------------------------------------------------------------------- John F. Lussen Vice President, Taxes U.S.A. -------------------------------------------------------------------------------------------------------------------- Brian J. Smith Assistant Secretary U.S.A. --------------------------------------------------------------------------------------------------------------------
                           JOINT FILING AGREEMENT


         This will confirm the agreement by and between the undersigned
that the Schedule 13D filed on or about this date and any amendments
thereto with respect to beneficial ownership by the undersigned of shares
of the Common Stock, par value $.001 per share, of Vysis, Inc. is being
filed on behalf of each of the undersigned under the Securities Exchange
Act of 1934, as amended. This agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

Dated:  November 1, 2001

                                     ABBOTT LABORATORIES


                                     By:  /s/ RICHAED A. GONZALEZ
                                          ----------------------------
                                          Name:  Richard A. Gonzalez
                                          Title: Executive Vice President,
                                                 Medical Products


                                     RAINBOW ACQUISITION CORP.


                                     By:  /s/ THOMAS C. FREYMAN
                                          ---------------------------
                                          Name:  Thomas C. Freyman
                                          Title: Vice-President