Koc/cefe/Ier 
University jig 
J 9 
OI 
THE ROCKEFELLER UNIVERSITY 
1230 YORK AVENUE • NEW YORK, NEW YORK 100 21 
December 6, 1979 
Dr. Donald S. Fredrickson, M.D. 
Di rector 
National Institutes of Health 
Public Health Service 
Department of Health, Education, and Welfare 
Bethesda, .Maryland 20014 
Dear Dr. Fredrickson: 
I am writing to suppo 
binant DMA experiments per 
as category P-1 experiment 
make this amendment to the 
the best scientific advice 
delayed the category chang 
response. I believe that 
sistent with public safety 
mate health related resear 
to proceed. 
rt the decision to reclassify recom- 
formed in Escherichia col i strain K-12 
s. I understand that a decision to 
guidelines was made on the basis of 
but that the Secretary of H.E.W. has 
e pending an assessment of the public 
the category change is fully con- 
, and is essential to permit legiti- 
ch dependent upon cloning techniques 
Sincerely yours, 
Thomas P. Toomey 
Biomedical Fellow 
[ 438 ] 
