14 December 1979
Dear Dr. Fredrickson:
I am writing to urge you in the strongest possible terms to approve the new version of the NIH Guidelines for Recombinant DNA Research, proposed in the Federal Register of November 30, 1979.  In particular, I would like to emphasize, as have many others, the importance of the section (III-0) which would relax regulations governing experiments which employ E. coli K12 host-vector systems.  There is now ample risk assessment on both sides of the Atlantic (from the Rowe and Martin groups here and from Fried et al in Europe) to show what the vast majority of microbiologists had long predicted about the dangers of recombinant DNA work with this system.  Compared with other risks of modern laboratory lift (e.g., chemicals, fires, radioisotopes), the risks of this work appear trivial; the likelihood that E. coli K12 can behave as a pathogen has always been very small; and the bureaucracy that has mushroomed to deal with recombinant DNA is now an impediment to the productive pursuit of scientific objectives.  The new proposal is a reasonable response to such arguments.  Ultimately, I believe that even the registration of experiments with E. coli K12 can be dispensed with, but the step recommended by your Advisory Council seems to me to be a satisfactory beginning.
Sincerely,
Harold E. Varmus
Professor
Department of Microbiology and Immunology