41 
Dr. Cavalieri 
In his discussion of the probability values which can be assigned to 
a potential accident in DNA recombinant research, Dr. Cavalieri 
suggested that it is impossible to make such calculations. He refers to 
the hundreds of operations required in such research, each of which 
could involve some error leading to an accident, and suggested that 
no meaningful risk-benefit calculation could be made of these processes. 
Furthermore, some researchers in this field believe that it is possible 
to characterize a DNA fragment as being “pure”, that is, uncon- 
taminated by some unidentified fragment which might be carrying 
unknown traits. The ability to characterize with precision the DNA 
fragment which is to be cloned is an important part of the safety 
precautions being developed for DNA recombinant work. Cavalieri is 
concerned because of work completed in England which suggests 
that a “pure” fragment of DNA may in fact contain overlapping 
information which might code for a second protein other than the one 
associated with the fragment. In his opinion, the presence of unex- 
pected fragments in a so-called “pure” fragment of DNA introduces 
an additional question regarding the reliability of the guidelines. He 
further suggested that the authors of the NIH guidelines had not 
taken this possibility into consideration during their development of 
the guidelines. 
Dr. Cavalieri also stated that the coupling of a low probability of 
accident with a high risk event is a value judgment requiring societal 
and not scientific examination as to the policy course which should be 
followed. This is one of the factors which led him to his position that 
the discussions about this area of research should be public and that 
the researchers should not be making the final decisions about the 
continuation of the research. 
Dr. Whelan 
With regard to risk assessment experiments on an international 
level, Dr. Whelan indicated that the European Molecular Biology 
Organization is constructing a P4 facility and that this 'site (in 
Heidelberg) might be the location of any experiments of this type. 
Dr. Cape 
In his comments on risk-benefit analysis, Dr. Cape supported the 
views of a number of other observers. The points he considered most 
important included: (1) in the assessment of unknown risks compared 
to benefits, which of these are certain cannot be made by debate, and 
these uncertainties must be evaluated experimentally; (2) any indica- 
tion of “diabolical” efforts in genetic engineering, particularly in- 
volving human beings, should be prohibited; (3) DNA recombinant 
research should not be the “whipping boy” for general concern about 
the impact of scientific developments on society and changes in science 
policy. 
Dr. Singer 
During her panel discussion, Dr. Singer indicated that she perceived 
that there were more areas of agreement than disagreement with 
regard to the use of the D NA recombinant molecule research method. 
[Appendix B — 90] 
