165 
Dr. Shaw? 
DR. SHAW: On the embryological question that he raised, I am con- 
cerned, too, about the pristine quality of embryonic DNA. I think that we 
don't know enough about how viruses are integrated into the genome. We cer- 
tainly do know in man that there are dominant genes that are inherited and 
are certainly present in the zygote DNA, and we are addressing ourselves 
only to the question of foreign viruses that infect later. I think we must 
keep in mind that the native DNA of a number of organisms may have cancer 
potential. 
DR. GOLDSTEIN: It is not just even animal cells. The same analogy 
exists in JE. coli , the organism of choice. There have been papers published, 
the last one by Ira Herskowitz in virology dealing with cryptic phages. 
Now, lambda is one of the vectors to be used, and what one would want to do 
is make a crippled lambda so that one could control it. The best way to do 
that would probably be through deletion mutants. You actually eliminate a 
certain gene so it couldn't package or so it couldn't make a tail, or some 
other important function, essential function. 
But what Herskowitz has shown is that lambda genes are present in IS. 
coli , not complete genomes, but lambda genes, and they therefore can rescue 
any cryptic which is going to be — any crippled vector which is going to be 
used. 
DR. FREDRICKSON: Thank you, Dr. Goldstein. I think we really have to 
move on. 
DR. GOLDSTEIN: Shall I give the second talk? 
DR. FREDRICKSON: You have a second talk? 
DR. GOLDSTEIN: Yes. It is the talk I was supposed to give yesterday. 
DR. FREDRICKSON: How long will it take you, Dr. Goldstein? 
DR. GOLDSTEIN: Less than 10 minutes. I will try. 
DR. FREDRICKSON: I think I will have to ask you to step down for a 
moment to see if we have time before we do continue. 
DR. GOLDSTEIN: Sure. 
DR. FREDRICKSON: Otherwise we certainly want you to provide that to us 
in writing. 
DR. GOLDSTEIN: That was the statement that was given out. I don't 
know if the committee has it. 
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