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                                                                   EXHIBIT 10.33

                            STOCK PURCHASE AGREEMENT

     This Stock Purchase Agreement ("Agreement") is made effective as of June
30, 1999 by and between deCODE genetics, Inc., a Delaware corporation (the
"Company"), and each of the undersigned.


                              PRELIMINARY STATEMENT

     A.   Each of the undersigned wishes to purchase from the Company, and the
Company wishes to sell to each of the undersigned, the number of shares of the
Company's Series B Preferred Stock, par value US$0.001 per share ("Series B
Preferred Stock"), set forth opposite each of the undersigned's signature or
such other number as may be agreed upon by the undersigned and the Company (the
"Shares").

     B.   The parties wish to provide for the terms and conditions of the
purchase and sale of the Shares.

     NOW, THEREFORE, in consideration of the premises and the mutual promises
hereinafter set forth, the parties hereby agree as follows:

     1.   Sale and Purchase of Shares.

          (a) Upon the terms and subject to the conditions set forth in this
Agreement and upon the representations and warranties made herein, the Company
shall sell, grant, convey, assign, transfer and deliver to the undersigned, and
the undersigned shall purchase and acquire from the Company, the Shares. Upon
Closing under this Agreement, all of the Shares shall be fully paid and
nonassessable.

          (b) In exchange for issuance of the Shares, each of the undersigned
agrees to pay to the Company $7.50 per share (the "Purchase Price") on the
Closing Date (as defined below). The Purchase Price shall be payable by
certified or bank check or by wire transfer or other immediately available funds
to the Company to such bank accounts as designated by the Company in writing. It
is understood that such payment may come from the undersigned or its affiliates.

          (c) The closing of the sale to, and purchase by, the undersigned of
the Shares (the "Closing") shall occur at the offices of the Company on or
before July 31, 1999 or such other date as the parties shall mutually agree (the
"Closing Date").

          (d) At the Closing, the Company shall deliver to each of the
undersigned stock certificates representing the Shares, registered in the name
of each of the undersigned, against payment of the amount of the Purchase Price
as set forth above.

     2.   Representations and Warranties of Undersigned. By executing this
Agreement, each of the undersigned:




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          (a) acknowledges that it understands that as a condition to the
Company's sale of the Shares to the undersigned, the undersigned must become a
party to that certain Amended and Restated Investor Rights Agreement by and
among the Company and the other parties thereto (the "Investor Rights
Agreement"), dated as of February 2, 1998, a copy of which has been provided to
the undersigned, that execution of this Agreement shall constitute execution of
the Investor Rights Agreement, and that the Shares and the shares (the
"Conversion Shares") of Common Stock of the Company, par value US$0.001 per
share, issued upon conversion of the Shares may be transferred only in
accordance with the provisions of the Investor Rights Agreement;

          (b) represents and warrants that the undersigned is able to bear the
economic risk of losing the undersigned's entire investment in the Shares and
has such knowledge and experience in business and financial matters and with
respect to investments in securities to enable the undersigned to understand and
evaluate the risks of ownership of the Shares and to form an investment decision
with respect thereto;

          (c) acknowledges that a copy of the Amended and Restated Certificate
of Incorporation of the Company (the "Certificate of Incorporation") which
describes the relative rights and preferences of the Series B Preferred Stock
has been provided to it and that all material documents, records and books
pertaining to this investment have, on request, been made available to the
undersigned's advisors and the undersigned;

          (d) acknowledges that the Company has made available to the
undersigned and the undersigned's representatives the opportunity to ask
questions of, and receive answers from, the Company concerning the Company and
the transaction contemplated hereby;

          (e) represents and warrants that the undersigned received, executed
and deposited for delivery to the Company this Agreement at the address set
forth on the signature page below;

          (f) represents and warrants that the undersigned is not a "U.S.
person," as such term is defined in Regulation S ("Regulation S") promulgated
pursuant to the Securities Act of 1933, as amended (the "Securities Act"), a
copy of which definition has been provided to the undersigned, is not purchasing
the Shares for the account or benefit of a "U.S. person" and if the undersigned
is other than an individual, that the undersigned was not formed by a "U.S.
person" principally for the purpose of investing in securities not registered
under the Securities Act;

          (g) understands that the Shares and the Conversion Shares are subject
to substantial restrictions on transfer in the United States and to "U.S.
persons" and that, except as set forth in the Investor Rights Agreement, the
Company has no obligation to take any action to make such transfers possible;

          (h) agrees that the undersigned will resell the Shares and Conversion
Shares only in accordance with the provisions of Regulation S, or pursuant to
registration under the Securities Act or to an exemption therefrom, and will not
engage in hedging transactions with regard to the Shares and Conversions Shares
unless in compliance with the Securities Act. Furthermore, the




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undersigned agrees that the Company shall refuse to register any transfer of the
Shares or Conversion Shares not made in accordance with the provisions of this
subsection 2(h); and

          (i) acknowledges that, if the undersigned is purchasing the Shares
subscribed for hereby in a fiduciary capacity, the above representations and
warranties in this Section 2 shall be deemed to have been made on behalf of the
person or persons for whom the undersigned is so purchasing.

     3.   Indemnification. The undersigned acknowledges that the undersigned
understands the meaning of the representations made by the undersigned in this
Agreement and that the Company will rely upon the truth and accuracy of such
representations. The undersigned hereby agrees to indemnify and hold harmless
the Company and all persons deemed to be in control of the Company from and
against any and all claims, actions, loss, costs, expenses, damages and
liabilities (including, without limitation, court costs and attorneys' fees)
arising out of or due to a breach by the undersigned of any such
representations. All representations shall survive the delivery of this Stock
Purchase Agreement and the purchase by the undersigned of any Shares.

     4.   Restrictions on Transfer. The undersigned hereby agrees with the
Company as follows:

          (a) In addition to the restrictions on transfer imposed by the
Investor Rights Agreement, the undersigned will not transfer the Shares or the
Conversion Shares, or any of them, in the United States or to a "U.S. person"
unless registered under the Securities Act or unless the Company has received an
opinion of counsel satisfactory to the Company and its counsel that such
registration is not required.

          (b) In addition to the legend set forth in Section 2.1(b) of the
Investor Rights Agreement, the certificates evidencing the Shares that the
undersigned has agreed to purchase and the Conversion Shares, and each
certificate issued in transfer thereof, will bear legends substantially as
follows:

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED (THE "1933 ACT") OR THE SECURITIES ACT OF ANY STATE AND
THEY MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED, PLEDGED OR HYPOTHECATED
UNLESS AND UNTIL REGISTERED UNDER THE 1933 ACT AND APPLICABLE STATE SECURITIES
ACTS OR, IN THE OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE
ISSUER OF THESE SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE OR
HYPOTHECATION IS PURSUANT TO AN AVAILABLE EXEMPTION FROM SUCH REGISTRATION OR IS
IN ACCORDANCE WITH THE PROVISIONS OF REGULATION S UNDER THE ACT. HEDGING
TRANSACTIONS INVOLVING THESE SECURITIES MAY NOT BE CONDUCTED UNLESS IN
COMPLIANCE WITH THE ACT.

     5.   Pre-Closing Covenants. Prior to the Closing, the Company hereby
covenants and agrees to:




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          (a) Obtain the consent of its Board of Directors to the transactions
contemplated hereby;

          (b) Obtain the consent of its stockholders and all other required
consents or approvals of third parties to the transactions contemplated hereby;

          (c) File an amendment to the Certificate of Incorporation with the
Secretary of State of Delaware which increases the number of authorized shares
of Series B Preferred Stock from 5,000,000 to 1,000,000; and

          (d) Take all other actions which are necessary or proper in connection
with the transactions contemplated hereby.

     6.   Conditions to Closing. The obligation of the undersigned to purchase
the Shares shall be conditioned on the Company's performance of each of the
covenants set forth in Section 5 hereof. If at the Closing any of such covenants
shall not have been fulfilled to the reasonable satisfaction of any the
undersigned, such undersigned, at its election, shall be relieved of all further
obligations under this Agreement.

     7.   Miscellaneous.

          (a) Should any one or more of the provisions of this Agreement be
determined to be illegal or unenforceable, all other provisions of this
Agreement shall be given effect separately from the provision or provisions
determined to be illegal or unenforceable and shall not be affected thereby.

          (b) The internal substantive laws, without regard to the laws of
conflicts, of the State of Delaware shall govern this Agreement. The parties
hereto hereby irrevocably submit to the exclusive jurisdiction of any Delaware
state or federal court sitting in the State of Delaware, for any action or
proceeding arising out of or related to this Agreement, and the parties hereto
hereby irrevocably agree that all claims in respect of any such action or
proceeding may be heard and determined in Delaware state court or, to the extent
permitted by law, in such federal court. The parties hereto hereby irrevocably
waive, to the fullest extent they may effectively do so, the defense of an
inconvenient forum to the maintenance of any such action or proceeding.

          (c) This Agreement constitutes the entire agreement between the
parties hereto pertaining to the subject matter hereof and supersedes any and
all prior or contemporaneous agreements or understandings of the parties
relating to the subject matter hereof. All such agreements shall terminate and
be of no further force or effect.

          (d) This Agreement may be executed in any number of counterparts and
by different parties hereto in separate counterparts, with the same effect as if
all parties had signed the same document. All such counterparts shall be deemed
an original, shall be construed together and shall constitute one and the same
instrument.




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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed on their behalf.


                                      deCODE genetics, Inc.



                                       By:    /S/ Kari Stefansson
                                             ---------------------------
                                             Kari Stefansson, President




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                                 SIGNATURE PAGE
                                       TO
                            STOCK PURCHASE AGREEMENT
                                       AND
                            INVESTOR RIGHTS AGREEMENT



                                   PURCHASER:

                                   By:    /s/ Yves Schmit   /s/ Carine Bittler
                                        ---------------------------------------

                                   Name:  Biotek Invest S.A.

                                   Title: Director

                                   Date: June 30, 1999

                                   Address: 41 Avenue de La Gare
                                            L-1611 Luxemburg

                                   Number of Shares Being Purchased:   5,000,000




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                              DECODE GENETICS, INC.

                      ADDENDUM TO STOCK PURCHASE AGREEMENT

     This Addendum to Stock Purchase Agreement (this "Addendum"), is made as of
February 24, 2000 (the "Effective Date") by and between deCODE genetics, Inc., a
Delaware corporation (the "Company"), and Biotek Invest, S.A. (the "Purchaser").

                             PRELIMINARY STATEMENTS

     A.   On June 30, 1999 the Company and the Purchaser entered into a Stock
Purchase Agreement pursuant to which the Purchaser agreed to purchase from the
Company 5,000,000 shares (the "Series B Shares") of the Company's Series B
Preferred Stock (the "Series B") at a price (the "Original Purchase Price") of
US$7.50 per share.

     B.   Contemporaneously with the execution of the Stock Purchase Agreement,
the Company and the Purchaser entered into an oral agreement pursuant to which
they agreed that the Original Purchase Price would be increased to $15.00 per
share (the "Adjusted Purchase Price"), with the amount in excess of the Original
Purchase Price (the "Contingent Payment") to be payable only if the Purchaser
were able to sell at least 50% of the Series B Shares at or above the Adjusted
Purchase Price and if the trading price in the Icelandic market, as determined
by agreement of the parties, remained at or above the Adjusted Purchase Price
from the time of such resale to the end of 1999.

     C.   The Company and the Purchaser further agreed that if the Contingent
Payment became payable, the Company would pay the Purchaser a commission of 7%
on the aggregate Adjusted Purchase Price and the Purchaser would pay the Company
interest at the rate of 6% per annum on the Contingent Payment from the date of
closing of the transaction under the Stock Purchase Agreement (the "Closing
Date"), to the date of payment of the Contingent Payment.

     D.   On August 8, 1999, the Closing Date, the Purchaser advised the Company
that it had arranged for the sale of at least 50% of the Series B Shares at a
price of $15.00.

     E.   On December 28, 1999, the Company and the Purchaser agreed that the
trading price in the Icelandic market had remained at or above the Adjusted
Purchase Price from August 8, 1999 through December 28, 1999 and that the
Purchaser would pay the Contingent Payment plus interest but net of commission,
on or before February 25, 2000.

     NOW, THEREFORE, the parties hereto, intending to be legally bound, agree as
follows:

     1.   ADJUSTMENT TO PURCHASE PRICE; PAYMENT OF DEFICIENCY. The parties
hereby confirm that the conditions for the Contingent Payment were satisfied.
The Purchaser has paid the Company the sum of US$ 33,476,712 representing the
Contingent Payment, with interest thereon less the Commission (as defined
herein).



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     2.   COMMISSION. The Purchaser has received a credit against the Contingent
Payment in the amount of US$5,250,000 (the "Commission"), representing 7% of the
total aggregate Adjusted Purchase Price for the Series B Shares.

     3.   MISCELLANEOUS. This Addendum shall be governed by and construed
under the laws of the State of Delaware as applied to agreements among Delaware
residents made and to be performed entirely within the State of Delaware. Except
as otherwise expressly provided herein, the provisions hereof shall inure to the
benefit of, and be binding upon, the successors, assigns, heirs, executors, and
administrators of the parties hereto. This Addendum, together with the Stock
Purchase Agreement, constitutes the full and entire understanding and agreement
among the parties with regard to the subject matter hereof. This Addendum may be
executed in any number of counterparts, each of which shall be deemed an
original and all of which together shall constitute one instrument. Except as
set forth herein, all terms of the Stock Purchase Agreement remain unchanged and
in full force and effect.

                                     *******


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     This Addendum to Stock Purchase Agreement is hereby executed to be
effective as of the date first above written.


                                  deCODE genetics, Inc.



Dated: 24.02.2000                 By:  /s/ Hannes Smarason
                                  Name: Hannes Smarason
                                  Title: Senior Vice President


                                  Biotek Invest, S.A.


Dated: 24.02.2000                 By:  /s/ Yve Schmidt
                                  Name: Yve Schmit
                                  Title: Director