Dr. Fredrickson 
3 
15 May 1978 
for recombinant DNA molecules, the recent development of transformation 
systems for Streptomyces (in David Hopwood ’ s laboratory in England and in 
my laboratory), in photosynthetic pseudomonads, in Rhizobium , and in other 
organisms that make products of considerable biological or medical import- 
ance parallels the discovery made earlier this year in yeast, and these 
advances are changing the situation rapidly. Work in non-E. coli K12 
organisms is proceeding at a rapid pace in Eastern and Western Europe; 
however, unless the wording of the proposed guidelines is changed, current 
work of great medical and social value will halt in the United States — 
simply because the drafters of this section of the revised guidelines did 
not, in my opinion, give thoughtful consideration to the implications of 
the wording. This matter is made worse because of the apparent adminis- 
trative errors on two separate occasions, which kept discussion of this 
problem off the committee's agenda. 
Don, if the system is going to work, the guidelines must have some 
internal consistency and rationality. I hope that you will see fit to 
modify the section dealing with HV1 hosts when you issue your final version 
of the revised guidelines. I would be glad to discuss the matter further 
with you or your staff by telephone if this would be useful to you. 
With best regards, 
Stanley N. Cohen, M.D. 
Professor of Medicine and 
Professor of Genetics 
Ends 
cc: William J. Gartland, Jr 
[Appendix A — 308] 
