Dr. Donald S. Fredrickson 
October 23, 1979 
Page 2 
I, therefore, urge in the strongest terms that guidelines for containment of 
tumor virus gene-splicing experiments be raised to P4-EK2 levels rather than be 
further weakened as would result form the E. coli K-12 exemption proposal 
of the September, 1979 RAC meeting. 
I have enclosed a copy of a letter written to Nature before the announcement 
of the proposed exemptions, indicating my belief that there was cause for concern 
even under the existing guidelines. 
Sincerely, 
Stuart A. Newman 
Associate Professor of Anatomy 
SAN/emk 
[ 360 ] 
