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                                                                  EXHIBIT 10.25

                               SUBLEASE AGREEMENT


This Sublease Agreement, made as of the ___ day of January, 2001 by and between
DISCOVERY COMMUNICATIONS, INC., having an office at 7700 Wisconsin Avenue,
Bethesda, Maryland 20814 ("Sublandlord"), and INFORMAX, INC., having an office
at ____________________("Subtenant");

                               W I T N E S S E T H

        WHEREAS, by Office Lease dated August 14, 1998, (the "Overlease"),
Newlands Building Venture, LLC ("Landlord"), leased to Sublandlord, as tenant,
approximately 75,391 square feet of rentable area on the floors of the building
located at Two Bethesda Metro Center, Bethesda, Maryland (hereinafter referred
to as the "Building"), at the rent and upon and subject to the terms and
conditions set forth in the Overlease; and

        WHEREAS, Subtenant desires to sublet from Sublandlord the entire third
(3rd) and fourth (4th) floors under lease to Sublandlord;

        NOW, THEREFORE, the parties hereto, for themselves, their successors and
assigns, mutually covenant and agree as follows:

        1. Demised Premises. Sublandlord does hereby demise and sublease to
Subtenant, and Subtenant does hereby sublease from Sublandlord, for the term and
upon the conditions hereinafter provided, an area of approximately 34,849 square
feet of rentable area consisting of the entire third (3rd) and fourth (4th)
floors of the Building (such area being hereinafter referred to as the "Demised
Premises"). The Demised Premises is indicated by outlining and diagonal marking
on the floor plan attached hereto and made a part hereof as Exhibit A.

        2. Condition. The Demised Premises are subleased to Subtenant upon and
subject to the terms and conditions herein set forth, in their "as is" condition
existing on the date possession is delivered to Subtenant, without requiring any
alterations, improvements, repairs or decorations to be made by Sublandlord, or
at Sublandlord's expense, either at the time possession is given to Subtenant or
during the entire term of this Sublease, or any extension thereof. In connection
therewith, Subtenant represents that it has thoroughly examined the Building and
the Demised Premises. Sublandlord provides no representation or warranty that
the Building, main lobby, restrooms and other common areas of Building, comply
with the Americans with Disabilities Act (the "ADA"), building codes, or with
other fire and safety codes, or any other representation or warranty except as
expressly provided herein.

        3. Term. The term of this Sublease shall commence on March 1, 2001, and
shall end on July 31, 2004. In the event Landlord's consent has not been
obtained by _____________, 2001, or such later date as Sublandlord and Subtenant
may agree to in writing, this Sublease shall be and become null and void and of
no further force or effect and all Prepaid Rent and the Security Deposit (as
defined in Section 11 of this Sublease) shall be promptly returned to Subtenant.


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        4. Monthly Base Rent. The monthly base rent which Subtenant hereby
agrees to pay to Sublandlord in advance, and Sublandlord hereby agrees to
accept, shall be the sum of One Hundred Twenty One Thousand Nine Hundred Seventy
One and 50/00 Dollars ($121,971.50) (hereinafter referred to as "Monthly Base
Rent"), commencing at the beginning of the term of this Sublease and continuing
thereafter on the last day of each and every calendar month during the term of
this Sublease. The Monthly Base Rent payable by Subtenant hereunder shall be
increased on the first anniversary of the commencement of the term and on each
anniversary thereafter by an amount equal to three percent (3%) of the Monthly
Base Rent. If the obligation of Subtenant to pay rent hereunder begins on a day
other than on the first day of a calendar month rent from such date until the
first day of the following calendar month shall be prorated at the rate of
one-thirtieth (1/30th) of the monthly installment for each day payable in
advance.

        5. Operating Expenses and Real Estate Passthroughs. Beginning on the
first anniversary of the sublease commencement date and each anniversary
thereafter, Subtenant will pay to Sublandlord, on an annual basis, its
proportionate share of any increases in Operating Expenses and Real Estate Taxes
as may occur over a base year of 2001, subject to the provisions of the
Overlease. Subtenant's proportionate share of Sublandlord's obligations under
the Lease is 46.22%.

        6. Payments. The Monthly Base Rent, Additional Rent and any other
charges herein reserved or payable shall be paid to Sublandlord at 7700
Wisconsin Avenue, Bethesda, Maryland 20814, Attention: ______, or at such
other place as Sublandlord may reasonably designate in writing, in lawful money
of the United States of America without demand therefor and without and
deduction, setoff or abatement whatever, except as expressly provided in this
Sublease.

        7. Use. Subtenant will use and occupy the Demised Premises solely for
general office purposes and in accordance with the use permitted under the
applicable zoning regulations. Without the prior written consent of Landlord and
Sublandlord, the Demised Premises will not be used for any other purposes.

        8. Alterations. Subtenant shall not make any alteration, improvement,
decoration, or installation (hereinafter called "Alterations") in or to the
Demised Premises without Sublandlord's consent, not to be unreasonably withheld,
conditioned or delayed but subject nevertheless to Landlord's consent. If any
Alterations are made without consent, Landlord or Sublandlord may remove the
same, and may correct, repair and restore the Demised Premises and any damage
arising from such removal, and Subtenant shall be liable for any and all costs
and expenses incurred by Landlord or Sublandlord in the performance of this
work.

        9. Furniture Equipment and Improvements. Sublandlord shall provide the
Subtenant beneficial use of the systems furniture, chairs, file cabinets,
kitchen equipment and substantial leasehold improvements within the Premises.
Subtenant agrees to maintain all the equipment and improvements in the Premises
in good condition, subject only to normal wear and tear, or to repair and
replace the same as necessary at Subtenant's sole cost and expense. In
consideration to rental rate paid, the equipment and furniture shall become the
property of the Subtenant at the end of the sublease Term. Prior to the
commencement of this Sublease, Sublandlord shall provide a detailed inventory of
all equipment and furniture which will be conveyed to Subtenant, and the parties
shall agree to a written amortization/buyout schedule for such equipment and


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furniture in the event of an early termination of this Sublease.

        l0. Parking. Sublandlord shall use commercially reasonable efforts to
assist Subtenant in securing a ratio of parking contracts in the Building
parking garage similar to that contained in the Overlease; provided, however,
Sublandlord makes no warranty or representation to Subtenant regarding: (1)
obtaining monthly parking contracts or (2) the use of the parking garage.
Subtenant agrees to contract the garage operator directly in trying to obtain
monthly parking contracts. Rates for any parking contract shall be at the
then-prevailing parking rates charged by the garage operator.

        11. Security Deposit and Prepaid Rent. Upon execution of Sublease,
Subtenant shall deposit with Sublandlord a sum equal to One Hundred Twenty-One
Thousand Nine Hundred Seventy One and 50/100 Dollars ($121,971.50) as a
non-interest bearing cash deposit to cover payment of Base Rent for the first
calendar month of the Sublease Term ("Prepaid Rent"). In addition, upon
execution of Sublease, Subtenant shall deposit with Sublandlord as security for
rent furniture, fixtures and equipment, either: (1) an additional non-interest
bearing cash deposit of One Hundred Twenty-One Thousand Nine Hundred Seventy One
and 50/00 Dollars ($121,971.50), or (2) an unconditional and irrevocable letter
of credit in favor of Subtenant in customary form and issued directly by PNC
Bank or other bank, having one or more offices in the Washington, D.C.
metropolitan area, having an expiration date not earlier than one (1) month
after the expiration date of the Sublease Term ("Security Deposit").

        12. Terms of Overlease. All of the terms, provisions, covenants and
conditions of the Overlease are incorporated herein by reference and hereby made
a part hereof (other than the following provisions of the Overlease: Sections 1,
2, 4, 6, 8, 34, 41). As between the parties hereto, Subtenant hereby assumes all
of the obligations of the Sublandlord, as the tenant under the Overlease but
only to the extent they are applicable to the Demised Premises. Sublandlord
shall have all of the rights but not the obligations of the Landlord under the
Overlease as against Subtenant and, Sublandlord agrees to observe and perform
the terms, covenants and conditions on its part to be observed and performed
hereunder as well as those applicable terms, covenants and conditions to be
observed and performed by Landlord under the Overlease with respect to the
Demised Premises. Notwithstanding anything in this Sublease to the contrary,
Subtenant agrees that Sublandlord shall not be obligated to furnish for
Subtenant any services of any nature whatsoever, including, without limitation,
the furnishing of heat, electrical energy, air conditioning, elevator service,
cleaning, window washing, or rubbish removal services, however, Sublandlord
shall be obligated to take all action necessary to obtain the performance of and
furnishing of such services for the Demised Premises by Landlord pursuant to the
terms of the Overlease. Subtenant shall obtain and maintain all insurance types
and coverages as specified in the Overlease to be obtained and maintained by
Sublandlord, as tenant, in amounts not less than those specified in the
Overlease. All policies of insurance obtained by Subtenant shall name Landlord
and Sublandlord as additional insureds therein in accordance with the Overlease.
Subtenant's insurance shall be primary over Landlord's and Sublandlord's
insurance with respect to the Demised Premises. Subtenant will deliver to
Sublandlord at the commencement of the Sublease term and on demand thereafter
certificates reflecting that Subtenant has obtained and is maintaining the
required insurance coverages in the appropriate amounts.

        13. Overlease. Sublandlord hereby represents and warrants to Subtenant
that attached hereto as


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Exhibit B is a true, correct and complete copy of the Overlease; that the
Overlease is in full force and effect; and that to the best of Sublandlord's
knowledge there are no defaults thereunder by any party. Subtenant acknowledges
the attached Overlease that it has reviewed the Overlease, and that it is
familiar with the contents thereof.

        14. Subtenant's Covenants. Subtenant covenants and agrees that Subtenant
will not do anything which would constitute a default under the Overlease or
omit to do anything which Subtenant is obligated to do under the terms of this
Sublease and which would constitute a default under the Overlease.

        15. Indemnification. (a) Subtenant shall and hereby does indemnify and
hold Landlord and Sublandlord harmless from and against any and all actions,
claims, demands, damages, liabilities and expenses (including, without
limitation, reasonable attorneys' fees) asserted against, imposed upon or
incurred by Landlord or Sublandlord by reason of (a) any violation caused,
suffered or permitted by Subtenant, its agents, servants, employees or invitees,
of any of the terms, covenants or conditions of the Overlease or this Sublease
and (b) any damage or injury to persons or property occurring upon or in
connection with the use or occupancy of the Sublandlord, or its agents,
employees or invitees.

        (b) Sublandlord shall and hereby does indemnify and hold Subtenant
        harmless from and against any and all actions, claims, demands, damages,
        liabilities, and expenses (including, without limitation, reasonable
        attorney's fees) asserted against, imposed upon or incurred by Subtenant
        by reason of (a) any violation caused, suffered or permitted by
        Sublandlord, its agents, servants, employees, or invitees, of any of the
        terms, covenants or conditions of the Overlease or this Sublease and (b)
        any damage or injury to persons or property occurring upon or in
        connection with the use or occupancy of the Sublandlord, or its agents,
        employees, or invitees.

        16. Assignment and Sublease. (a) Subtenant agrees not to assign,
mortgage, pledge or otherwise encumber this Sublease, nor to sublet the Demised
Premises or any part thereof, without the consent of the Sublandlord, which
consent shall not be unreasonably withheld, conditioned or delayed. Any
assignment or sublease shall be in strict accordance with the terms, conditions
and restrictions of the Overlease.

        (b) Notwithstanding anything to the contrary herein, but subject
        nevertheless to the Overlease, Subtenant may assign this Sublease or
        sublet all or part of the Demised Premises either to a wholly owned
        corporation or entity or controlled subsidiary or parent of the
        Subtenant or to any successor to Subtenant by purchase, merger,
        consolidation or reorganization (hereinafter collectively referred to as
        "Corporate Transfer") without consent of Sublandlord (but not without
        prior written consent from Landlord in accordance with Section 7(A) of
        the Overlease), provided that (i) Subtenant is not in default under this
        Sublease; (ii) if such proposed transferee is a successor to Subtenant
        by purchase, said proposed transferee shall acquire all or substantially
        all of the stock or assets of Subtenant's business or, if such proposed
        transferee is a successor to Subtenant by merger, consolidation, or
        reorganization, the continuing or surviving corporation shall own all or
        substantially all of the assets of Subtenant; (iii) such Corporate
        Transfer shall be subject to the terms of this Sublease; (iv) in the
        case of an assignment, such proposed


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        transferee shall have a net worth which is equal to or greater than
        Subtenant's net worth at the date of this Sublease; and (v) in the case
        of assignment, such proposed transferee shall assume all of the
        obligations of Subtenant hereunder. Subtenant shall give Sublandlord and
        Landlord written notice at least thirty (30) days prior to the effective
        date of any such Corporate Transfer. As used herein, the term
        "controlled subsidiary" shall mean a corporate entity wholly owned by
        Subtenant or at least fifty-one percent (51%) of whose voting stock is
        owned by Subtenant.

        17. Confidentiality. All terms and conditions contained in the Overlease
and in this Sublease shall be treated as confidential information and shall be
shared only with those parties necessary to execute and perform the transaction
throughout the entire term of this Sublease.

        18. Brokers. Sublandlord and Subtenant hereby represent and warrant
that except for (i) Freeman Group LLC/Gerstein Commercial Realty and (ii)
Newmark and Bank Company, neither party has dealt with any broker in connection
with this Sublease for the Demised Premises, and Subtenant will defend and hold
harmless Sublandlord from any loss arising from breach of this. Sublandlord will
be responsible for any commissions, payments or fees due to said brokers
pursuant to a separate agreement.

        19. Entire Agreement. This Sublease contains all of the covenants,
agreements, terms, provisions, conditions, warranties and understandings
relating to the leasing of the Demised Premises and Sublandlord's obligations in
connection therewith, and neither Sublandlord nor any agent or representative of
Sublandlord has made or is making, and Subtenant in executing and delivering
this Sublease is not relying upon, any warranties, representations, promises or
statements whatsoever, except to the extent expressly set forth in this
Sublease. All understandings and agreements, if any, heretofore had between the
parties are merged to this Sublease, which alone fully and completely expresses
the agreement of the parties. The failure of Sublandlord to insist in any
instance upon the strict keeping, observance or performance of any covenant,
agreement, term, provision or condition of this Sublease or to exercise any
election herein contained shall not be construed as a waiver or relinquishment
for the future of such covenant, agreement, term, provision, condition or
election, but the same shall continue and remain in full force and effect. No
waiver or modification of any covenant, agreement, term, provision or condition
of this Sublease shall be deemed to have been made unless expressed in writing
and signed by Landlord and Sublandlord. No surrender of possession of the
Demised Premises or of any part thereof or of any remainder of the term of this
Sublease shall release Subtenant from any of its obligations hereunder unless
accepted by Sublandlord in writing. The receipt and retention by Sublandlord of
monthly base rent or additional rent from anyone other than Subtenant shall not
be deemed a waiver of the breach by Subtenant of any covenant, agreement, term
or provision of this Sublease, or as the acceptance of such other person as a
tenant, or as a release of Subtenant of the covenants, agreements, terms,
provisions and conditions herein contained. The receipt and retention by
Sublandlord of monthly base rent or additional rent with knowledge of the breach
of any covenant, agreement, term, provision or condition herein contained shall
not be deemed a waiver of such breach.

        20. Successors and Assigns. The obligations of this Sublease shall bind
and benefit the successors and permitted assigns of the parties with the same
effect as if mentioned in each instance where a party hereto is named or
referred to.


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        21. Notices. Any and all communications delivered hereunder shall be
sent in accordance with the provisions of Section 31 of the Overlease, as
follows: If to Landlord c/o the Chevy Chase Land Company of Montgomery County,
Maryland, Suite 540, Two Wisconsin Circle, Chevy Chase, Maryland 20815; if to
Sublandlord, 7700 Wisconsin Avenue, Bethesda, Maryland 20814 Attention:
_________; and if to Subtenant 6010 Executive Boulevard, Rockville, Maryland
20852, Attention: Sandy Terry, with a copy to Hogan & Hartson L.L.P., 8300
Greensboro Drive, Suite 1100, McLean Virginia 22102, Attention: Dennis K. Moyer,
Esq.; or to such other address and attention as any of the above shall notify
the others in writing.

        22. Landlord's Consent. This Sublease shall be effective upon obtaining
the written consent of Landlord, or its duly authorized agent, and it is hereby
acknowledged by Sublandlord and Subtenant that Landlord's consent to this
Sublease shall not create any contractual liability or duty on the part of
Landlord or its agent to the Subtenant, and shall not in any manner increase,
decrease or otherwise affect the rights and obligations of Landlord and
Sublandlord, as the tenant under the Overlease, with respect to the Demised
Premises.

        23. Amendments. Sublandlord and Subtenant shall not amend this Sublease
without Landlord's prior written consent, and any such amendment made or entered
into without Landlord's consent shall be null and void.


        24. Limitation on Damages. Each party waives any right to consequential
damages against the other.


                            [SIGNATURE PAGE FOLLOWS]







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        IN WITNESS WHEREOF, Sublandlord and Subtenant have duly executed this
Sublease as of the day and year first above written.


WITNESS/ATTEST:                                SUBLANDLORD:

                                DISCOVERY COMMUNICATIONS, INC.


                                By:    /s/ DOMENICK FIORAVANTI
                                      --------------------------------------
                                Name: Domenick Fioravanti
                                      --------------------------------------
                                Its:  SVP ADMIN OFFICER
                                      --------------------------------------
                                                (SEAL)


WITNESS/ATTEST:                                 SUBTENANT:

                                INFORMAX, INC.


                                By:    /s/ TIMOTHY D. SULLIVAN
                                      --------------------------------------
                                Name: Timothy D. Sullivan
                                      --------------------------------------
                                Its:  EVP
                                      --------------------------------------
                                                (SEAL)

        This Sublease is consented to by the Landlord by and through its duly
authorized agent, the Chevy Chase Land Company of Montgomery County Maryland,
upon the terms acknowledged by Sublandlord and Subtenant in the paragraph of
this Sublease entitled "LANDLORD'S CONSENT."


                                          LANDLORD:

                                          NEWLANDS BUILDING VENTURE, LLC

                                          By:  The Chevy Chase Land Company of
                                               Montgomery County Maryland, Agent

                                            By:
                                                --------------------------------
                                                Name:
                                                       -------------------------
                                                Title:
                                                       -------------------------


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