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EXHIBIT 23.1
Consent of Ernst & Young LLP, Independent Auditors
We consent to the incorporation by reference in the Registration Statement
on Form S-8 pertaining to the 1997 Stock Option Plan, of Maxygen, Inc., 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
May 24, 2000
