Margo G. Haygood p. 2 
start and modified subsequently only if there is a substantiated 
change in the assessed risks". 
In order for any useful evaluation of the adequacy of the guide- 
lines to occur, there must be more information about both the 
degree of hazard and the adequacy of containment. For this 
reason I urge that NIH should pursue, under stringent safety 
precautions, experimentation bearing on these questions. Of 
particular interest is the question of whether eukaryotic genes 
are ever expressed in prokaryotes. If not, then the rlsks'of 
experiments inserting eukaryotic DNA into prokaryotes may be 
judged to be considerably lower than would be the case if such 
genes were indeed expressed. 
Physical Containment - No form of physical containment can be con- 
sidered totally effective - we must assume that a breach will 
occur eventually. I am not convinced that PI and P2 as generally 
practiced will provide substantial protection. Any exper- 
iment in which escape of laboratory organisms is judged at all 
hazardous should not depend on these means. 
Nonetheless, technique is the key to safe procedure, but tech- 
nique is highly dependent on the attitude of the worker. Dr. 
Shaw's suggestions regarding consent procedures could possibly 
serve a dual role in this regard. workers could be required to 
sign a consent form indicating that tney understand the risks 
of the research. ana are trained in strict microbiological tech- 
nique. Such a procedure would provide a mechanism for informing 
workers of the nature of the risks to which they and the public 
will be exposed, as well as for certifying their competence. 
Further, it might serve as a "consciousness-raising" device, 
periodically reminding workers that they are working with hazard- 
ous materials. This procedure might help to avoid the sloppi- 
ness and casual attitude that often arises from routine handling 
of dangerous substances. 
Biological Containment * In many respects biological containment 
is the key to our hope of avoiding release of dangerous organisms, 
as no form of physical containment is entirely effective. I 
share the misgivings of may of the public witnesses about the 
use of any form of E. coir as a standard experimental organism. 
I urge that NIH make a concre te committment to the development of 
a vector-host system with a less ubiquitous natural distribution, 
and more limited capacity for exchange of genetic information 
with other organisms. 
Further, serious thought should be given to methods for inducing 
researchers to switch from use of E. coli , as it is clear that 
those accustomed to work with E. coli will be reluctant to change. 
I do not propose an immediate ban on E. coli , because, although 
I am not convinced that Dr. Berg's claim that it will take an- 
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