SEPTEMBER 6-7 - MINUTES OF MEET I EX] 
12 
Mr. Schwartz, representing the Senate Subcommittee on Science, Technology 
and Space, asked that since the recombinant polyoma dimer is infectious, 
doesn't this represent a new route for an infectious agent to get into 
an organism and cause a tumor. Ct. Rowe stated that the dimer recombinant 
carried by bacteria did not produce tumors. Dr. Schwartz then asked how 
far such data can be extrapolated. He noted that the experiment has not 
been done with herpes virus. Dr. Rowe commented that polyoma has a 
small genome with a relatively small region required for transformation. 
He said that this favors the validity of the experiment. Dr. Novick 
said that if the RAC does not agree on the principle that one can extra- 
polate, then there will have to be risk-assessment studies on every 
single experiment. He said that he favors the principle of extrapolation. 
Dr. Campbell stressed that the proposed exemption does not deal with 
wild- type E. coli and that the prohibitions are not being relaxed. 
Dr. Rowe stated that there have been no surprises in the experiments. 
Dr. Novick said that extrapolations have to be made on the best possible 
available information. We will never have incontrovertible data on 
every possible point. 
Dr. Baltimore said that the polyoma experiments were originally suggested 
because polyoma offered a sensitive model system about what recombinant 
DNA might do in an organism. There was agreement that if polyoma "got 
out" and was active, the signal would be obvious. He said that the 
results have been clearer and less worrisome than he would have thought. 
He said that he had thought that polyoma DNA in E. coli would likely 
cause an infection. Mr. Dach of EDF said he agreed that you cannot do 
experiments on every conceivable risk, but that one or two additional 
risk-assessment experiments might be useful. Dr. Krimsky asked about 
the probability of an outcome in other systems even though other test 
systems might not be as sensitive. Dr. Baltimore reiterated that the 
sensitivity of other systems, such as herpes, would be much lower than 
the polyoma system. He said that he does not think that a better alternative 
model exists. He noted that antigenic conversion in the polyoma system 
is more sensitive than lethality. 
Dr. Novick said that he felt that there are three conceivable hazards. 
He felt that the virus question has been adequately settled. He felt 
that concerns about the immunogenic ity question are minimal or zero. 
However, he expressed concern over the issue of active polypeptides, and 
suggested that the exemption might be worded in such a way as to exclude 
situations involving active polypeptides from the exemption. Dr. Baltimore 
said that he would want to have a positive reason to worry about the poly- 
peptide problem. 
Dr. Brill said that he did not think that E. coli carrying foreign DNA 
would be maintained in the gut and would lose the foreign DNA unless it is 
under positive selective pressure. He also said that he feels transmission 
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