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Exhibit 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in Amendment
No. 1 to the Registration Statement (Form S-3) and related Prospectus of
Maxygen, Inc. for the registration of 209,500 shares of its common stock and to
the incorporation by reference therein of our report dated February 18, 2000,
with respect to the financial statements of Maxygen, 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
Palo Alto, California
January 18, 2001
