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classification of experiments, and when you start talking about the classi- 
fication of experiments, you are immediately into the biological and physical 
containment, because these are the things that are cited. 
From ray perspective, and I have spent some time considering this, 
and I am involved in some recombinant DNA experimentation from a different 
point of view than most of the people here that are involved in the work, 
I feel that biological containment is more important than physical contain- 
ment. I think it gives you a greater degree of control and it is a greater 
concept of safety associated with biological containment than physical 
containment. Now, the case in point is, if you take a look at PI and P2, 
there is no difference in terms of the facility. What we are talking about 
is a set of techniques or a set of mental concepts that we say constitute 
P2 activity versus PI activity, and if you proceed to the types of experi- 
ments that can be performed under P2+EK2 conditions, it is equivalent to a 
P3+EK1 experiment. I would prefer to see the P2+EK2, and get away with the 
lower physical containment. Now, that is a personal judgment on my part. 
If you take a look at the safety factors of the various EK2 systems, 
the lambda system versus the 1776, the lambda will lyse. If something 
is released into the environment and it grows under the unrestricted con- 
ditions of whatever it encounters, the system lyses. That is part of the 
system. That is part of the biological containment. The idea is to grow 
the lambda systems for a reasonable amount of time, they lyse, you collect 
the viable DNA, and then you go through another round of this for ampli- 
fication. But that is a value judgment, and those are my thoughts. 
DR. FREDRICKSON: Dr. Liberman, I think you have a lot to tell us, and 
I want to break in to ask you a couple of questions. In reference to the 
experimental Guidelines, are you generally in favor of the revisions, or 
opposed to them, and if you have specific points, would you mention them 
very quickly? 
DR. LIBERMAN: Well, it is difficult to mention quickly. I told Bill 
before — I am sorry, Dr. Gartland — that I would address the specifics in 
writing, because I think there are several here. 
DR. FREDRICKSON: Very good. That would be very helpful. 
DR. LIBERMAN: I basically feel that we have over-contained in terms 
of the physical containment concepts of it, and that we could probably get 
away with lower physical containment, but at least really looking at the 
biological containment phase of it, many of the risk experiments that Pro- 
fessors Rowe and Martin want to do can be done at P3+EK2. I believe that. 
DR. FREDRICKSON: We will be looking forward to that. 
DR. LIBERMAN: Okay, the other point that I want to make is that — and 
it is again talking about E. col i as a pathogen — now, no one in here will 
doubt the fact that E. col i can cause urinary tract infections, it can cause 
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