7 
although there was considerable disagreement as to the degree of pos- 
sible or probable hazard posed by recombinant DNA activities, as well 
as just how restrictive the legislation should be. Most witnesses, how- 
ever, believed that the safety standards set forth in the NIH Guide- 
lines would, if properly enforced, provide adequate protection to pub- 
lic health and the environment. 
During the spring and summer of 1977, there Was growing opposi- 
tion to legislation to regulate recombinant DNA activities among cer- 
tain scientists. The basis for the opposition, was, in part, the publiciz- 
ing of new data demonstrating that the possibility of rendering E. coli 
K-12 an epidemic pathogen by the insertion of recombinant DNA 
was virtually nonexistent. Furthermore, the recent development of 
plasmid vectors with very low transfer frequencies would make the 
inadvertent transfer of recombinant DNA to known pathogens very 
unlikely. These data were elucidated in a letter to Dr. Fredrickson 
from Dr. Eoy Curtiss III, then a member of the NIH Eecombinant 
DNA Molecule Program Advisory Committee, and discussed further 
at an NIH sponsored workshop on risk assessment held at Falmouth, 
Mass., on June 21-22, 1977. 
Dr. Sherwood Gorbach, chairman of the Falmouth workshop, stated 
in a letter to Dr. Fredrickson summarizing the discussion, “The par- 
ticipants arrived at unanimous agreement that E. coli K-12 cannot be 
converted into an epidemic pathogen by laboratory manipulations 
with DNA inserts.” Since most, but by no means all, recombinant 
DNA activities use the E. coli K-12 host, some scientists drew the con- 
clusion that not only was legislation to regulate recombinant DNA 
activities unnecessary, but that the NIH Guidelines, themselves were 
largely superfluous. However, such a conclusion was not generally 
shared by the participants at Falmouth. Dr. Bruce Levin, a Falmouth 
participant wrote, also in a letter to Dr. Frederickson, “. . . this (con- 
sensus) is a very comforting conclusion, but it is only part of the 
story. There remains the possibility that recombinant DNA carried 
by the “safe” hosts could be transferred to more invasive strains of 
E. coli , other enteric bacterial species or even the somatic cells of their 
metazoan hosts.” In fact, the Falmouth participants concluded that 
more feeding experiments were necessary to adequately assess the 
transfer of DNA plasmids from E. coli K-12 to other strains. There 
was little or no discussion of a number of other potential hazards of 
recombinant DNA manipulations, including animal virus-mammalian 
host cell combinations, or of plant host- vector combinations. Dr. Levin 
concludes his letter, “I don’t believe that evidence available through 
existing efforts at risk assessment is sufficient to justify a relaxation of 
the current NIH Guidelines on recombinant DNA research or of the 
efforts to enforce them”; There was general consensus at Falmouth 
on the continued need to observe the NIH Guidelines. 
It is the view of the committee that as long as there remain areas of 
recombinant DNA research where potential hazards are recognized 
to the degree that the best informed scientists agree that safety guide- 
lines should be observed, legislation is necessary to extend such safety 
standards to all public and private parties, and to provide a means to 
enforce them. However, the committee recognizes that as data on the 
relative safety of recombinant DNA activities accumulate, the strin- 
gency of particular standards should be changed to reflect the best 
fi. Kept. 95-1005 2 
[Appendix B— 137] 
