95 
worrying about what E. coli is carrying that we put in, and that is a very 
different issue, first of all. 
Second of all I think we are talking about a difference in scale in 
the operation between what molecular biologists and biochemists want to 
do compared to what you have been doing over the last 25 years. You deal 
with them as small cultures, either in diagnostic work or for studies on 
a small scale. We want to be able to grow them in large quantities and 
isolate the molecules they carry, and I believe it is the scale which 
raises the questions about risk more so than the level you have talked 
about . 
The third point, which I have only alluded to, is that we are not 
talking about individuals who are trained medical microbiologists or 
people who have grown with an experience and background in dealing with 
pathogenic microorganisms. I think we all recognize that if we were 
dealing with only those people we would only have to call to their atten- 
tion the potential risk of certain experiments, and they would be well- 
enough trained to handle it. 
When we drafted the initial report to the Academy, we recognized 
that the enormous influx of people into this field without that back- 
ground, without that training and without that experience, but with this 
great familiarity, an almost contemptible familiarity with JE. coli as 
being an innocuous organism. I think the issue we are raising now is 
that _E. coli carries something. It is not E. coli, it is what it carries. 
And two, we are dealing with it on a scale which is different than has been 
done before; and three, it is being worked on by people who have not had 
the training or the background. Hopefully these guidelines will now 
force people to acquire that training and to use the best available tech- 
niques that you people have worked out over the last 25 years. 
DR. PETERSDORF : But you know, the R factors that the jE. coli carry 
hasn't done anything to its pathogenicity, even in man. So you are talk- 
ing really about potential hazards and the speculation has to be. Now, 
I won't address myself to the scale situation which I can't comment on, 
and to the training thing which I agree with you on. The real speculation 
is what is the potential hazard? And just because E^. coli carries some- 
thing, does that enhance its pathogenicity? For that you have no evidence, 
as far as I can tell. 
DR. BERG: We agree, then. 
DR. FREDRICKSON: I think Dr. Curtiss wants to respond to this very 
same point. 
DR. CURTISS: I would just like to add on to what Dr. Berg has said. 
I agree with him, but there are some additional things. 
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