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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 the
Registration Statement (Form S-3) and related Prospectus of Maxygen, Inc. for
the registration of 199,500 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
December 14, 2000
