Exhibit 99.1

                             [LOGO OF ZYMOGENETICS]

Contact
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INVESTOR RELATIONS                              MEDIA RELATIONS
John Calhoun, MD, MBA                           Susan W. Specht, MBA
Director, Corporate Communications              Corporate Communications Manager
& Investor Relations                            (206) 442-6592
(206) 442-6744

FOR IMMEDIATE RELEASE
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    GEORGE B. RATHMANN, PH.D. TO RETIRE FROM ZYMOGENETICS BOARD OF DIRECTORS

Seattle, February 15, 2006 - ZymoGenetics, Inc. (NASDAQ: ZGEN) announced today
that George B. Rathmann, Ph.D. will retire effective March 10, 2006 from the
company's Board of Directors for personal health reasons.

Dr. Bruce L.A. Carter, President and CEO, remarked, "George Rathmann has been
described as a legend in biotechnology. George is also a wonderful human being
and we are sorry to lose him as a board member but pleased he has accepted the
position of Chairman Emeritus. We are very grateful for his valuable
contributions over five years and we will continue to elicit his advice and
listen carefully to his counsel."

ABOUT ZYMOGENETICS
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ZymoGenetics is a biopharmaceutical company focused on the discovery,
development and commercialization of therapeutic proteins for the treatment of
human diseases. The Company is developing a diverse pipeline of potential
proprietary product candidates that are moving into and through clinical
development. These span a wide array of clinical opportunities that include
bleeding, autoimmune diseases and cancer. ZymoGenetics intends to commercialize
these product candidates through internal development, collaborations with
partners and out-licensing of patents from its extensive patent portfolio. For
further information, visit www.zymogenetics.com.

FORWARD LOOKING STATEMENTS
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This press release contains "forward-looking statements" within the meaning of
the Private Securities Litigation Reform Act of 1995. These forward-looking
statements are based on the current intent and expectations of the management of
ZymoGenetics. These statements are not guarantees of future performance and
involve risks and uncertainties that are difficult to predict. ZymoGenetics'
actual results and the timing and outcome of events may differ materially from
those expressed in or implied by the forward-looking statements because of risks
associated with our unproven discovery strategy, preclinical and clinical
development, regulatory oversight, intellectual property claims and litigation
and other risks detailed in ZymoGenetics' public filings with the Securities and
Exchange Commission, including ZymoGenetics' Annual Report on Form 10-K for the
year ended December 31, 2004. Except as required by law, ZymoGenetics undertakes
no obligation to update any forward-looking or other statements in this press
release, whether as a result of new information, future events or otherwise.

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