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EXHIBIT 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts"
in the Registration Statement (Form S-3) and related Prospectus of
Transkaryotic Therapies, Inc., for the registration of $500,000,000 of
securities and to the incorporation by reference therein of our report dated
February 4, 2000, with respect to the consolidated financial statements of
Transkaryotic Therapies, Inc. included in its Annual Report (Form 10-K) for
the year ended December 31, 1999, filed with the Securities and Exchange
Commission.
/s/ Ernst & Young LLP
Boston, Massachusetts
December 11, 2000
