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DR. FREDRICKSON: I see, all right. The record is clear. 
MR. BEATY: So it is an error then in the Federal Register. 
DR. TALBOT: The warm-blooded is the P3+EK3 and the cold-blooded is 
P3+EK2. They follow one another, and they look quite alike. 
DR. FREDRICKSON: Is that clear, Mr. Beaty? 
MR. BEATY: Yes. 
DR. FREDRICKSON: Now we turn to another area, in some ways equally as 
difficult, from the standpoint of some of us at least, and that is the 
matter of experiments with plants. I should say that we have attempted to 
serially increase the Recombinant Advisory Committee in regard to the com- 
petence in the plant area. There are now two members. We look to the op- 
portunity to present a third. 
Dr. Peter Day, who was to present this particular section, is ill; he 
could not be here today. Therefore, Dr. Zaitlin, who has recently joined 
the Committee, has very kindly agreed to summarize instead of Dr. Day. 
Dr. Zaitlin. 
DR. ZAITLIN: Thanks, Dr. Fredrickson. I am sure if Dr. Day were here, 
he would make an elegant plea for the use of recombinant DNA technique in 
plant work. I don't really think that is necessary. Obviously it is a tech- 
nique which is of interest to plant scientists, and I think there is a small 
number of people involved, but the interest is certainly growing. The in- 
terest in this has really been accelerated recently by the finding of Dr. 
Chilton and her colleagues that a plasmid of Agrobacterium tumefaciens is 
incorporated, at least in part, into the host genome. There are other 
vectors which are considered as probable for insertion of plant DNA into 
plant tissues, and amongst these are plant viruses. Unfortunately, most 
plant viruses are RNA viruses, and there are just two groups relatively 
restricted in their host range which are DNA plant viruses. One group is 
double-stranded DNA, and another involves single-stranded DNA viruses. So 
I think, actually, that plant viruses probably may have a limited role in 
being a vector in this sort of work. 
I would like to address myself to the proposed suggested changes in the 
Guidelines. These are three in number. The biggest one is, if you look at 
your Green Book at page 15, this is with respect to shotgun experiments. Now, 
the original Guidelines called for a higher level of containment for cloning 
DNA from plants that make a project known to be dangerous to any species. 
Now, this caused some problems because as an extreme example, all plants 
make CO 2 in the dark, which is toxic in high enough concentrations to most 
aerobes. So a strict interpretation would thus have called for P3+EK2 with 
plant DNA, and the Committee considered this unreasonable. 
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