64 
I became a vocal participant in the discussion on recombinant DNA mole- 
cule research soon after the publication of the Berg et al. letter of July 
1974. I have taken a rather consistent conservative attitude since that 
time in believing that the potential biohazards were far more likely to be 
real than unreal. 
I have therefore argued that one should err on the conservative side 
in stipulating containment conditions for any given experiment when in doubt 
about the potential biohazards, that terminology should be sufficiently 
well-defined to avoid ambiguity in interpretation, and that there should be 
a mechanism to assure that investigators were using the appropriate physical 
and biological containment systems and procedures. 
I was thus reasonably satisfied with both the Asilomar guideline state- 
ment and the draft guidelines prepared by Dr. Hogness and his subcommittee 
for presentation to the NIH Advisory Committee at our Woods Hole meeting. 
The outcome of that meeting, however, was to amend the draft to liber- 
alize the classification of some experiments, to muddy the definition of 
some important terminology, and of most concern to me, to reduce the safety 
requirements for E. coli K12 biological containment systems, and to permit 
almost anyone to designate a host or a vector as meeting EK2 standards on 
the basis of theoretical considerations and without a requirement for data 
to be presented to substantiate the claim. I thus voted no on the adoption 
of those guidelines. 
The La Jolla document which you all have, and which Dr. Singer de- 
scribed this morning, remedied all of these problems, and I was thus pleased 
and very much relieved at the end of that meeting to be able to cast a yes 
vote in favor of the adoption of these guidelines. 
In the summer of 1974 my lab group was initiating recombinant DNA mole- 
cule research and had begun to genetically manipulate El_ coli K12 strains 
to facilitate these endeavors. I thus conceived of the idea to also gene- 
tically alter E_j_ coli to make it safer for this research, and communicated 
these ideas to my colleagues who were drafting the suggested guidelines for 
recombinant DNA molecule research with prokaryotic organisms to be presented 
at the Asilomar conference. These proposals for the design of safer hosts 
and vectors are contained in an appendix to our report made at that meeting. 
Since Asilomar my group at the University of Alabama has worked full 
time in designing safer E. coli K12 hosts, and I must admit the task has 
been far more difficult than I or others ever imagined. Indeed, it was our 
difficulties last summer that caused me greatest concern about the guide- 
lines drafted at Woods Hole. 
I will now briefly describe our objectives and accomplishments during 
the past year in disarming coli K12. 
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