Dr. Fredrickson . 
- 3 - 
11/14/77 
3. Distribution of Certified Host-Vectors 
This section should also include new certified HV1 host- vector 
systems. 
III. Experimental Guidelines 
B. Containment Guidelines for Permissible Experiments 
1. Classification of Experiments Using the E.coli K-1Z Host- 
Vector System 
a. Shotgun Experiments 
This section remains unnecessarily restrictive and is in- 
consistent with the section on lower eukaryotic DNA's. 
We suggest eliminating the requirement for "extensive 
characterization" which could inadvertently eliminate all 
prokaryotic DNA's other than those of E. coll, lambda and 
T4 from the minimum containment of P2+KV1. Surely 
"shotgun" experiments to clone DNA from one non-pathogenic 
bacterium to another cannot pose a greater potential risk than 
"shotgun" cloning of plant or fungal DNA into a bacterium. 
We propose that cloning of DNA from non-pathogenic pro- 
karyotes requires only PE+HV1 or P1+HV2 containment. Clon- 
ing of DNA from Class 2 organisms could retain the P3+HV2 
containment requirement. However, care must be taken not to 
inadvertently include harmless microorganisms as Class 2 
agents ’(see Appendix A on classification of Actinomycetes ), 
since misclassification would impose the unfortunate and un- 
necessary requirement of increasing both the physical and bio- 
logical containment by one step. In practice, this could ef- 
fectively block any recombinant DNA research with the thera- 
peutically and economically important Streciomyces , since 
HV2 host- vector systems of this type will most certainly not 
be available for some time. Under these circumstances, the 
first paragraph of section HI., B. , a., 2. would not then be 
needed. 
b. Plasmids, Bacteriophages and Other Viruses 
There is little use in designating experimental guidelines for 
"permissible experiments" which cannot be met. This is the 
case for the classification "DNA viruses and DNA transcripts 
of retrovirus genomes". Furthermore, the designation of con- 
tainment for this class of experiments seems disproportionately 
conservative. Viruses in this class belong to the NCI category 
called "low-risk". In their naturally infectious forms, such 
viruses can be handled at what would correspond to a P2 level 
of containment. If we accept the Guidelines' conservative ap- 
proach of assigning recombinant organisms to levels "not less 
[Appendix A — 64] 
