161 
We recommend embryonic tissue because of its lack of exogenous viruses. 
The recommendation at that time did not include germs which I think you were 
referring to when you said separation from follicles. We are talking pri- 
marily about embryos, the fertilized, developing fetus. The reason germ- 
line cells remain here is because of a comment by Dr. Sidney Brenner, who 
recommended that they were another area of rather pristine, uninfected DNA, 
not carrying adventitious viruses. The way this occurred is that interest- 
ingly Dr. Brenner tried to justify the use of embryos. 
Dr. Brenner raised his hand and said, "Dr. Rowe, where do you place 
sperm?" Dr. Stetten said, "That is a very personal question." 
(Laughter. ) 
DR. FREDRICKSON: Mr. Hutt? 
MR. HUTT: I can't follow up on that. 
(Laughter. ) 
DR. GOLDSTEIN: Can I answer that question, the first question? 
I mean, I think you have a point in one area, in the sense of it being 
pure tissue, but embryonic tissue is still basic in the sense of it 
being defined in a vacuum, you still cannot define the genes that are 
there. That is still to me as dangerous as any other aspect of it. 
DR. FREDRICKSON: Mr. Hutt? 
MR. HUTT: I am unclear about your first point. You first stated that 
IS. coli should no longer be used, and then you concluded your first point by 
changing that, if I heard you, to saying that EK2 or EK3 should be used. 
Now, are you — am I simply misinterpreting you? 
DR. GOLDSTEIN: No, I will clarify that. I apologize if I wasn't clear. 
What I tried to say was that we still feel it is the wrong choice, but 
there is nothing else available. There is no better choice in the immediate 
sense. 
MR. HUTT: You are then saying that the experiments with EL coli should 
not be deferred, but you would in a sense recommend a three-step procedure, 
using EK1 until EK2 is available and then switch to EK2, and all the time be 
trying to develop something other than any form of _E. coli , and then move to 
that when it is available. 
DR. GOLDSTEIN: With a slight modification. I don't think EK1 should 
be used for all experiments. 
[302] 
