Dr. Donald S. Fredrickson 
February 5> 1976 
Page 3 
propellants. If it is discovered that these are a hazard their production can 
be halted and they will in time disappear. Not so with these organisms. 
What course of action would I, then, recommend? I would propose that all 
recombinant DNA work be performed under the highest possible precaution at 
one site in this country (Fort Detrick?) with the most extensive possible 
monitoring for the escape of such organisms into the environment. (I would only 
allow this because of the extraordinary benefits to be gained from such research). 
I would at the same time launch a major program to find a much more suitable 
host than E. coli for such work. The qualities of such a host should be 
a) that it is found and will grow only in very selected environments 
- thus if and when it escapes containment it will likely perish 
and in any event can be readily monitored; 
b) that it does not exchange DNA with any organisms in the normal 
human environment ; 
c) that it, of course, is non-pathogenic in itself, has suitable 
vectors , etc . 
I do not know the ideal organism for this purpose, but I would look among the 
thermophiles that live in hot springs, etc. 
Obviously, neither I nor anyone else can say that if the present committee 
guidelines are adopted, disaster will ensue. I will say, though, that, in my 
judgement, if the guidelines are adopted and nothing untoward happens, we will 
owe this success far more to good fortune than to human wisdom. 
I do not envy you your task. 
cc : Dr. Stetten 
Signed in Dr. Sinsheimer's absence 
With best wishes, 
'c d irC , 
Robert L. Sinsheimer 
Chairman 
[ 438 ] 
