UNIVERSITY OF CALIFORNIA, SAN FRANCISCO 
BERKELEY • DAVIS • IRVINE • LOS ANGELES • RIVERSIDE • SAN DIEGO • SAN FRANCISCO 
SANTA BARBARA • SANTA CRl'Z 
SCHOOL OF Ml DR INK 
SAN FRANCISCO, CALIFORNIA 94143 
Department of Microbiology 
and Immunology 
17 December 1979 
Dr. Donald Fredrickson 
Director, 
National Institutes of Health 
Bethesda, Maryland 20014 
Dear Dr. Fredrickson: 
I am writing to lend my whole-hearted approval to the proposed revisions 
in the National Institutes of Health guidelines for research with recombinant 
DNA. In particular, I commend to you the recommendations for reduction of most 
experiments employing E. coli K-12 to PI containment and for the simplification 
of registration and certification procedures. On the basis of experimental 
findings over the past several years, I am convinced that the present restric- 
tions are unnecessarily stringent. I have based this conclusion on two major 
facts: first, extensive and persuasive testing at NIH indicated that ingestion 
of bacteria bearing chimeric DNA carries no measurable risks to the host organ- 
ism; second, expression of vertebrate genes in bacterial hosts has generally 
occurred only as a result of deliberate and sophisticated experimental manipu- 
lations- and the revised guidelines provide for continued regulation of such 
deliberate efforts. 
The present procedures for regulating research with recombinant DNA have 
had deleterious effects on biomedical science in the United States: they have 
measurably slowed the pace of progress in several important disciplines; they 
have added significantly to the cost of this research; and they have demeaned 
the community’s effort to control forms of experimentation that carry genuine 
and commonly acknowledged risks. I believe that both the public and the cause 
of science would be well served by the proposed revisions in the NIH guidelines. 
PtQfessor 
Department of Microbiology 
and Immunology 
JMD : kw j 
