SEPTEMBER 6-7 - MINUTES OF MEETING 
9 
Dr. Gottesman raised concern about some of the reported experiments. 
She noted that xl776 was the E. coli host in many of the experiments and 
questioned whether the result - would have been different if an EKl host 
had been used. She questioned how far the results can be generalized. 
She further noted that the conference at Ascot concluded that recombinant 
DNA is an unlikely route of viral infection. However, she said that the 
Ascot conference did not deal with viral products. In response to the 
last point, Dr. Rowe stated that there are no viral products that are 
toxic. Dr. Novick stated that xl?76 is more likely to undergo lysis 
than other E. coli strains and should release its DNA. Therefore, he 
said that it should be a strong argument if one does not observe infection 
in experiments using xl776. Dr. Gottesman said that she still feels 
that use of xL776 partially prejudices the case. Dr. Goldstein said 
that the results of Levy and Marshall show that the outcome depends on 
the host. Dr. Rowe said that use of x 1776 magnifies the chance of delivering 
the polyoma ENA, and that maximal doses were used. 
Dr. Goldstein mentioned the positive result obtained with the lambda 
recombinant containing a dimer of polyoma. He raised the question whether 
this was an unexpected result. Dr. Rowe stated that the Falmouth conference 
predicted that oligomers would give positive results because of looping-out. 
He said that the positive results were less frequent than expected, and 
emphasized that _E. coli xl776 carrying lambda-polyoma recombinants never 
gave an infection. Dr. Novick said that cloned polyoma is much less 
likely to cause tumors. Dr. Krimsky questioned the relationship of 
these results and other biohazards. He said that it appears that polyoma 
DNA cloned in E. coli is safer than polyoma, but he expressed concern 
about E. coli establishing itself in new environments. Dr. Gottesman 
said that the basic question is whether E. coli carrying polyoma ENA has 
the possibility of establishing itself and providing a new route of 
entry of polyoma DNA into cells. Dr. Rowe said that the experiments 
were designed to test to what extent functional DNA can move out of 
bacterial cells into mammalian cells. Dr. Martin said that the experiments 
had to be done in xl776. He said that experiments with wild- type E. coli 
will require a special exemption and will be a major undertaking. 
Mr. Thornton asked whether the experiments show how a tumor virus operates 
as opposed to how a toxin might operate. Dr. Martin said that there had 
been great concern about cloning animal viruses in E. coli , and noted that 
a key segment of polyoma DNA causes tumors. In response to a question by 
Mr. Thornton, Dr. Talbot indicated that E. coli would not be expected to 
pick up and incorporate polyoma DNA in an _in vivo situation. 
Dr. Gittesman questioned other possible outcomes, such as pathogenicity or 
antigenicity. Dr. Novick responded that comprehensive risk-assessment is 
impossible and that certain special examples, such as the cloning of tumor 
viruses, have to be selected. He said the question is whether other exemplary 
cases should be investigated. He noted that the cloning of toxins is 
prohibited. He also said that he feels that the immunity question has been 
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