HARVARD UNIVERSITY 
DEPARTMENT OF CHEMISTRY 
12 Oxford Street 
Cambridge , Massachusetts 02138 
US. A. 
December 18, 1979 
Dr. Donald Fredrickson 
Director, National Institutes of Health 
Bethesda, MD 20205 
Dear Dr. Fredrickson, 
I strongly support the revision of the recombinant DNA guidelines 
proposed in the Federal Register Vol. 44^ No. 232, Friday, November 30, 
1979, pp. 69210-69251. Indeed I support the RAC proposal that "recombinant 
DNA molecules that are propagated in E. coli K-12 hosts not containing 
conjugation-proficient plasmids or generalized tranducing phages, when lambda 
or lambdoid bacteriophages or non-conjugative plasmids are used as vectors, 
are exempt from the guidelines," but will accept the more conservative 
reduction of DNA research in E. coli K-12 to PI containment. 
Yours truly. 
Helga Boedtker, Ph. D. 
HB:ko 
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