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                                                                     EXHIBIT 21


                       SUBSIDIARIES OF APPLERA CORPORATION

                               AS OF JUNE 30, 2003
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                                                                                          State or Jurisdiction
Name                                                                                 of Incorporation or Organization
----                                                                                 --------------------------------
<S>                                                                                  <C>
Applera Overseas Corporation                                                        (New York, USA)
          Applied Biosystems Pty Ltd.                                               (Australia)
          Applied Biosystems (Canada) Limited                                       (Canada)
               Applied Biosystems/MDS SCIEX Instruments (1)                         (Canada)
          Applied Biosystems (Thailand) Limited                                     (Thailand)
          PE AG                                                                     (Switzerland)
          Applera France S.A.                                                       (France)
          PE (Sweden) AB                                                            (Sweden)
               PE Stockholm AB                                                      (Sweden)
                   Applied Biosystems Finland OY                                    (Finland)
          Applera Holding BV                                                        (The Netherlands)
               Applera Finance BV                                                   (The Netherlands)
                   Nelson Analytical GmbH                                           (Germany)
                   Applera Europe BV                                                (The Netherlands)
                        Applied Biosystems Holdings Limited                         (UK)
                            Applied Biosystems Ltd                                  (UK)
                            PE GB Ltd.                                              (UK)
               Applera Polska Sp.zo.o.                                              (Poland)
               Applera Magyarorszag Kft                                             (Hungary)
               Applera Ceska republic s.r.o.                                        (Czech Republic)
          Spartan Ltd. (2)                                                          (Channel Isles)
               Listronagh Company                                                   (Ireland)
          Applied Biosystems Asia Pte. Ltd.                                         (Singapore)
               Applied Biosystems Malaysia Sdn. Bhd.                                (Malaysia)
          Applera Holding GmbH                                                      (Germany)
               Applera South Africa (PTY) Limited                                   (South Africa)
               PE Manufacturing GmbH                                                (Germany)
                    Applied Biosystems Manufacturing GmbH                           (Germany)
               Applera Austria Handels GmbH                                         (Austria)
          Applied Biosystems Hong Kong, Ltd.                                        (Hong Kong)
          Applied Biosystems do Brasil Ltda.                                        (Brazil)
          ZAO PE Biosystems                                                         (Russia)
          Applied Biosystems Korea LLC (3)                                          (Korea)
          Applied Biosystems Taiwan Corporation                                     (Delaware, USA)
PE Corporation (NY)                                                                 (New York, USA)
         Applied Biosystems de Mexico S. de R.L. de C.V. (6)                        (Mexico)
         Applera Insurance Company Limited (6)                                      (Bermuda)
         PE FSC, Inc. (6)                                                           (U.S.Virgin Islands)
         Applera Hispania SA (6)                                                    (Spain)
Applera International, Inc.                                                         (Delaware, USA)
PE Korea Corporation                                                                (Delaware, USA)
Applied Biosystems China, Inc.                                                      (Delaware, USA)
GenScope, Inc.                                                                      (Delaware, USA)
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                                                                                          State or Jurisdiction
Name                                                                                 of Incorporation or Organization
----                                                                                 --------------------------------
<S>                                                                                  <C>
PerSeptive Biosystems, Inc.                                                         (Delaware, USA)
         Applera Deutschland GmbH                                                   (Germany)
         Applied Biosystems Japan, Ltd.                                             (Japan)
         PerSeptive Biosystems (Canada) Ltd.                                        (Canada)
PNA Diagnostics ApS                                                                 (Denmark)
Boston Probes, Inc. (4)                                                             (Delaware, USA)
Paracel, Inc.                                                                       (California, USA)
         Paracel Government Systems, Inc.                                           (Delaware, USA)
Axys Pharmaceuticals, Inc.                                                          (Delaware, USA)
         Axys 468 Littlefield LLC                                                   (California, USA)
Foster City Holdings, LLC                                                           (Delaware, USA)
         Celera Diagnostics, LLC (5)                                                (Delaware, USA)
Rockville Holdings, LLC                                                             (Delaware, USA)
         Celera Diagnostics, LLC (5)                                                (Delaware, USA)

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Note: Entities directly owned by subsidiaries of Applera Corporation are
indented and listed below their immediate parent. Ownership is 100% unless
otherwise indicated.

(1)    50.0% ownership

(2)    51.0% ownership by Applera Overseas Corporation, and 49% by Applera
       Europe BV (indirectly wholly owned by Applera Corporation)

(3)    20.0% ownership by Applera Corporation, and 80.0% by Applera Overseas
       Corporation (directly and indirectly, in the aggregate, wholly owned by
       Applera Corporation)

(4)    84.9% ownership by Applera Corporation, and 15.1% by PNA Diagnostics ApS.
       (directly and indirectly, in the aggregate, wholly owned by Applera
       Corporation)

(5)    50.0% ownership by Foster City Holdings, LLC and 50% ownership by
       Rockville Holdings, LLC (indirectly wholly owned by Applera Corporation)

(6)    Applera Corporation consummated an internal reorganization of certain of
       its assets effective as of the end of its 2002 fiscal year. As part of
       this reorganization, ownership of these entities has been transferred by
       PE Corporation (NY) to Applera Corporation subject to obtaining necessary
       governmental clearances

Applera Corporation conducts its business through its Applied Biosystems Group,
its Celera Genomics Group, and its Celera Diagnostics joint venture between
these two groups. Applera Corporation and its direct and indirect wholly owned
subsidiaries conduct business under the names of these businesses and variants
thereof. In addition, Boston Probes, Inc., Paracel, Inc., and Axys
Pharmaceuticals, Inc. may from time to time conduct business under their
respective corporate names and variants thereof.

Applied Biosystems/MDS SCIEX Instruments conducts business under its business
name and variants thereof.