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minority on this Committee who would be qualified, perhaps, to interpret 
those experiments, which I feel a responsibility to the Committee for, but 
I can't interpret experiments when I haven't seen the results. 
It is not that I distrust the workers who have done the experiments. 
I just feel a need to examine them personally. I also, for example, trust 
Hal Ginsberg when he tells me that K-12 is not a good pathogen. I believe 
him. But that doesn't mean, to my mind, that it couldn't be made, somehow, 
a better pathogen. Pathogens in this world come to a kind of equilibrium 
with their hosts. 
Furthermore, the evidence as I have heard it which relates to the 
unlikelihood that K-12 could colonize humans doesn't help me very much with 
the possibility that K-12 could transfer their plasmids, for example, to other 
organisms in varied circumstances which simply have not been investigated 
in nature. 
In another sense, the existing Guidelines reflect a kind of — to my 
mind, they are sort of floating on an ordinate of hazard. You have heard 
various opinions, and are accepting the new data at face value — not having 
seen it, but accepting it. One can still be left with the fact that the 
absolute level of hazard is floating. Those who thought that the Guidelines 
were ludicrous, if they accept the new data, will now think they are even 
more lucidrous, as we heard this morning. Those who thought the Guidelines 
in the past were inadequate may still feel that they are inadequate. It is 
still not possible to establish an absolute level of hazard. 
To take up just a few specific questions — and I will try to write it 
in more detail — a few matters that concern me particularly, one was the 
matter of introducing new host-vectors. I was surprised and a little dis- 
turbed this morning to learn, for example, that experiments had been approved 
using Bacillus subtilis as a potential host-vector. It seems to me that in 
view of all the concern that has been expressed about K-12 — in view of all 
the knowledge we have about K-12 — that the introduction of another vector or 
other vectors should be preceded by very extensive and full public analysis 
of all the potential circumstances surrounding such a vector. In other words, 
with what other organisms might plasmids from that vector be exchanged? what 
other organisms are the potential victims or objects of attack by such a 
vector? and so on. In other words, when you bring in subtilis you bring in a 
whole different environment with which you have to be concerned than when you 
talk about col i . And so on when you bring in Streptomyces or whatever. 
To make a couple of very specific comments, I am fully in favor of 
the revisions that would allow the Director some discretion in regard to 
so-called forbidden experiments. I think that is necessary in order to 
allow risk assessment experiments. At the same time I think I would caution 
against that kind of trend to say that, well, because such-and-such an 
experiment has now been allowed somewhere else, it should be allowed here. 
That could lead to to a kind of endless roulette. 
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