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WRITER’S DIRECT DIAL NUMBER 
February 20, 1976 
TELEPHONE: (202) -452-6000 
(202) 452-6300 
TWX: 7IO 622-0005 
TELEX: 69-593 
CABLE: COVLING 
EDWIN S. COHEN 
OF COUNSEL 
Donald S. Fredrickson, M.D. 
Director 
National Institutes of Health 
Building 1, Room 124 
9000 Rockville Pike 
Bethesda, Maryland 20014 
Dear Don: 
This letter is in response to your request that each 
of the members of the Ad Hoc Advisory Committee which met with 
you on February 9-10 to consider the proposed guidelines for 
research on recombinant DNA molecules furnish you with specific 
conclusions and recommendations. Although most of the comments 
set out below will repeat observations I made during the two 
days of the meeting, and particularly in my remarks at the end 
of the meeting, I thought it might be helpful to summarize 
them in one place. 
From all the materials I have read on this subject 
and all that I heard at the meeting, there is no doubt in my 
mind that it is in the best interests of the public to proceed 
at this time with scientific research on recombinant DNA mole- 
cules. Although risks unquestionably exist, they are in no 
way insurmountable and, in any event, with appropriate control 
appear to be substantially less than the benefits to be obtained. 
Thus, the critical need is to devise control mechanisms to 
reduce the risks to a level that is low enough to be accept- 
able to the public, without at the same time raising unnecessary 
or onerous barriers to continuation of research in this field. 
I am confident that this balance can be struck. 
I 
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