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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the incorporation by reference to the Registration Statement (Form
S-8) of Affymetrix, Inc., pertaining to the Affymetrix/Neomorphic, Inc. 1998
Stock Option Plan, of our report dated February 8, 2000, except for the third
paragraph of Note 1 and Note 13 as to which the date is February 9, 2000, with
respect to the consolidated financial statements of Affymetrix, Inc. included in
its Current Report on Form 8-K dated April 7, 2000, filed with the Securities
and Exchange Commission.
/s/ Ernst & Young LLP
Palo Alto, California
December 21, 2000
