With regard to the section on Prokaryotic DNA Recombinants (Federal 
Register p. 49602), Dr. Botstein proposes that the second paragraph 
be modified as follows (Dr. Botstein' s proposed addition is under- 
lined): 
"Experiments with DNAs from bacteria that are not extensively 
characterized, require P2 physical containment + an EK2 host- 
vector or P3 + EK1. Experiments with DNAs from pathogenic 
species not known to recombine naturally with E. coli 
(Class 2 and plant pathogens, see Appendix B) must use 
P3 + EK2 . " 
Dr. Botstein also strongly felt that the CDC Classification of 
Etiologic Agents on The Basis of Hazard is out of date. 
[Appendix A — 105] 
