DEPARTMENT OF HEALTH. EDUCATION, AND WELFARE 
PUBLIC HEALTH SERVICE 
NATIONAL INSTITUTES OF HEALTH 
BETHESDA, MARYLAND 20014 
September 27, 1977 
Enclosed is a copy of proposed revisions of the NIH Guidelines on 
Recombinant DNA Research, as published in the Federal Register on 
Tuesday, September 27, 1977. These proposed revisions were referred 
to me on September 1, 1977, by the NIH Recombinant Advisory Committee, 
which had proposed the original Guidelines. The revisions were 
developed by the Committee on the basis of information accumulated on 
the effectiveness of physical and biological containment and on the 
biology of the hosts and vectors utilized in recombinant DNA research. 
I want to emphasize that these proposed revised Guidelines are not 
final and that the NIH Guidelines on Recombinant DNA Research, as pro- 
mulgated in July 1976, continue to govern NIH-supported or -conducted 
recombinant DNA research. These proposed revised Guidelines have been 
published for comment not only in the Federal Register but also in the 
NIH Recombinant DNA Technical Bulletin. This Bulletin is a new NIH 
publication that will attempt to link investigators involved in recom- 
binant DNA research in the United States ar abroad with the advisory 
groups and.- organi zat ions active in this ar 
Because of your stated interest in t development of the NIH 
Guidelines, I would appreciate your revi ing these proposed revisions. 
Your comments will be considered by me and by the Advisory Committee 
to the Director, NIH, at its December meet ng . On the basis of the 
comments received and review by the Advis' y Committee, I will subse- 
quently issue final Guidelines accompanie< jy a Decision document 
explaining the modifications. 
I welcome your comments on these proposed revisions to the NIH 
Guidel ines . 
Donald S. Fredrickson, M.D 
Director 
Enclosure 
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