EXHIBIT 15.1


August 9, 1999


The Board of Directors and Stockholders
Genentech, Inc.

We are aware of the incorporation by reference in the Registration Statements
pertaining to the 1999 Stock Plan, the 1996 Stock Option/Stock Incentive
Plan, the 1994 Stock Option Plan, and the 1990 Stock Option/Stock Incentive
Plan and in the related prospectuses, as applicable, contained in such
Registration Statements of our report dated July 9, 1999 relating to the
unaudited condensed consolidated interim financial statements of Genentech,
Inc. which are included in its Form 10-Q for the quarter ended June 30, 1999.

Pursuant to Rule 436(c) of the Securities Act of 1933 our report is not a
part of the registration statement prepared or certified by accountants
within the meaning of section 7 or 11 of the Securities Act of 1933.


Very truly yours,




/S/ERNST & YOUNG LLP
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Ernst & Young LLP