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What, if any, mechanism exists or can be made to exist that will effec- 
tively control the human error? I don't know the answer to this, but I 
really think it is a germane topic for this group to consider today. 
I will be happy to answer any other questions on the other points 
raised on the guidelines. I think my time is running short. Thank you. 
DR. FREDRICKSON: Dr. Zimmerman, the question that you raised initially 
of the force of the regulations and the nature of our consideration will be 
taken up a little bit later this morning, and I think I will ask the commit- 
tee to reserve further comment on that. 
If there are no urgent further questions for Dr. Zimmerman, then — thank 
you very much, Dr. Zimmerman. Your statement has been circulated and filed 
with us. 
I will proceed then to call upon the next witness. Dr. Sedat, Dr. John 
Sedat, from Yale University. Is that correct, Dr. Sedat? 
DR. SEDAT: Yes, it is. 
One tends to view this process actually in the here and now. This is 
1976, and we have a considerable amount of contemporary history of science 
to reflect on. For example, our reaction to nuclear power is quite dif- 
ferent now than it was in the early 40's, for example, and for example, we 
consider plutonium as a very extremely dangerous substance, and it doesn't 
even replicate. 
When you tend to reflect on this, one becomes sensitized to many issues 
that are actually hidden under the table. Let me give you some concrete 
examples . 
Most molecular biologists consider that the ultimate equalizer is the 
autoclave. You know, you want to kill everything, you toss it in the auto- 
clave and you can forget about it. However, when you start to reflect upon 
this, the DNA may not actually be killed by the autoclave, and we know, for 
example, the physical properties of the DNA in the cell, because it is topo- 
logically, covalently closed, may snap right back, and then when it gets 
tossed out down the drain, can easily infect the cell. You may knock it 
down a few logs or many logs, but when you consider you will have one liter 
of an infected culture, there are 10^ molecules there in that order, and 
that is a very large number. In any event, the molecules could easily be 
repaired in a recipient cell and the whole process started all over again. 
The other point is, you might well have two innocent systems in the lab 
going on. For example, one person might be just mapping a tumor virus with 
these same enzymes used to do the DNA recombination process, and in another 
end of the lab someone will be doing a simple bacterial DNA recombination 
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