157 
there can be some rather drastic kinds of reactions within our environment. 
I am just wondering, what is the justification for having these less restric- 
tive than the other ones. 
DR. ZAITLIN: I would disagree that they are less restrictive. 
DR. DE ROOS: Okay, that is what I was wondering. It didn't look to me 
like they were in here. 
DR. ZAITLIN: They talk about confining them to a P3 type of greenhouse. 
I don't even know whether such a greenhouse exists in this country; there 
may not be. So I don't think that at this stage those experiments could 
even be performed. 
DR. DE ROOS: So it is your conclusion that they aren't really less re- 
strictive, as was the conclusion that was drawn in this letter? 
DR. ZAITLIN: Actually, there are a number of other things in that let- 
ter which I would not agree with, particularly that case about the fungi and 
so forth. It has been shown that the controls do it too. It was reported 
in Sc ience . 
MR. HUTT: Isn't it animal virus PA and this is P3? 
DR. ZAITLIN: Well, this is P3, right, and it depends on whether or not 
you can confine the whole plant. There are some circumstances in which it 
even suggests perhaps PA, some experiments. 
MR. HUTT: Can we have some clarification as to whether it is or is not 
more restrictive? 
DR. FREDRICKSON: I think we will have to ask a third plant molecular 
biologist, or at least a second one. Dr. Chilton, what do you think? 
DR. CHILTON: As I read it, isn't the cloning of plant viruses P2+EK2? 
DR. ZAITLIN: No, it depends on whether or not you use the DNA of an un- 
modified plant virus, and then it is P3. But there are some qualifiers too, 
where in some circumstances it is PA. 
DR. FREDRICKSON: Are there any other questions or comments? 
MR. HUTT: I have major questions if we can't even get agreement as to 
what the requirements are. We need some clarity. 
DR. FREDRICKSON: Perhaps, Dr. Chilton, you want to examine what was 
just handed to you. 
MR. HUTT: It should be right in the Guidelines. 
DR. ZAITLIN: It is. 
[ 361 ] 
