Dr. Donald Fredrickson 
October 4, 1979 
Page Two 
even though of very low infectivity, could be created. It is thus apparent that 
initial concerns about the inadvertant endowment of new ecological niches for 
determinants of pathogenicity were justified. 
Fifth, although I know of no reason other than the above to suspect any hazard 
associated with recombinant DNA activities using E. col i K-12 host-vector systems, 
there must remain uncertainty since none of us is totally clairvoyant. Indeed, 
initial users of DDT, thalidomide and even the internal combustion engine were 
totally unable to predict the ultimate health hazards associated with their use. 
Also, most of the risk assessment experiments discussed and proposed by the 
participants at the Falmouth Conference (J. Infect. Dis. 117:704) have yet to 
be conducted and only recently have some of the more important studies been in- 
cluded in NIH's proposed risk assessment program (Federal Register, April 2, 1979). 
It would thus appear that the current Recombinant DNA Advisory Committee no longer 
considers the advice of the Falmouth participants or the data from the experiments 
they proposed to be relevant in assessing the risks of using the E_. col i K-12 
host-vector systems. 
Sixth, I should note that our laboratory uses recombinant DNA techniques for 
experiments requiring PI, P2 and P3 containment using donor DNA from eukaryotes 
and both pathogenic and non-pathogenic prokaryotes. Adherence to the NIH Guide- 
lines has not hindered our work. 
I therefore consider the exemption of all experiments using the E_. col i K-12 host- 
vector systems to be premature and not justified on the basis of objective review 
of available scientific evidence. I also believe that the Recombinant DNA Advisory 
Committee's recommendation to you was based more on the politics of science than 
on the data of science. 
^.Sincerely yours 
RCIII/pp 
cc: Dr. William Gartland 
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