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                                                                     EXHIBIT 5.1

June 8, 2001



Interleukin Genetics, Inc.
135 Beaver Street, 2nd Floor
Waltham, MA 02452


Gentlemen:

     We have acted as counsel for Interleukin Genetics, Inc., a Delaware
corporation (the "Company"), in connection with the authorization of 2,000,000
shares of common stock (the "Shares"), $.001 par value ("Common Stock"), of the
Company issuable pursuant to the Company's 2000 Employee Stock Compensation Plan
(the "Plan").

     In connection therewith, we have examined, among other things, the Plan,
the Certificate of Incorporation and By-Laws of the Company and the corporate
proceedings with respect to the issuance of the Shares and such other corporate
documents as we have deemed appropriate.

     Based on the foregoing, and having due regard for such legal considerations
as we have deemed relevant, we are of the opinion that the Shares to be issued
by the Company pursuant to the terms of the Plan have been duly authorized by
all requisite corporate action and, when issued in accordance with the terms
thereof, will be validly issued, fully paid and nonassessable.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our names in the Registration
Statement.

     The opinions expressed herein are limited exclusively to the General
Corporation Law of the State of Delaware and the federal securities law of the
United States of America.

     The opinions expressed herein are for your sole benefit and may be relied
upon only by you.

                                                 Very truly yours,



                                                 /s/ Fulbright & Jaworski L.L.P.