MASSACHUSETTS INSTITUTE OF TECHNOLOGY 
CENTER FOR CANCER RESEARCH 
77 MASSACHUSETTS AVENUE, CAMBRIDGE, MASSACHUSETTS 02139 
Room E17-529B 
December 12, 1979 
Dr. Donald Fredrickson 
Director of the NIH 
Bethesda, Maryland 20205 
Dear Dr. Fredrickson, 
I strongly support the revision of the guidelines so 
that DNA recombinant experiments involving the bacteria E^. coli 
are exempted. This is a prudent move and widely supported 
by the scientific community. 
Sincerely vours. 
Phillip A. Sharp 
Professor 
PAS /ms 
[ 462 ] 
