physical and biological containment by one step. In practice, 
this could effectively block any recombinant DNA research with 
the therapeutically and economically important Streptomyces , 
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 III., B. , a., 2. would not then 
be needed. 
c. Lowering of Containment Levels for Characterized or 
Purified DNA Preparations and Clones. 
1. Purified DNA Other than Plasmids, Bacteriophages, 
and Other Viruses. 
The first sentence of the last paragraph of this section could 
be modified in some manner to read, for example: "The institutional 
biohazards committee (IBC) must review and may approve such a 
reduc t ion" . 
Roles and Responsibilities. 
D. NIH Recombinant DNA Molecule Program Advisory Committee. 
The last sentence of the third paragraph of this section 
could be modified to take into account expertise in the field, 
for example: "in making recommendations for exceptions, weight 
will be given to scientific and societal benefits, potential 
risks, and to industrial experience with large scale production 
of pathogenic organisms and toxic materials”. This same 
modified statement should also appear in Section III., A., third 
paragraph. 
[Appendix A — 43] 
