23 
genetically altered by traditional microbiological genetic procedures 
to produce a dependence upon certain growth conditions and upon a 
particular host cell strain, also “crippled” to be dependent upon 
precise growth conditions. This combination of a sensitive vector for 
constructing the DNA recombinant molecule and a host cell for the 
cloning of the new DNA recombinant molecule is considered to be a 
significant part of the system which has evolved to permit the con- 
duct of DNA recombinant molecule research under extremely safe 
conditions. As pointed out by Dr. Curtiss, the use of the K-12 
strain of the bacterium Escherichia coli was due to the tremendous 
amount of information available on the genetics of this bacterium 
and the long laboratory experience in work including the initial 
DNA recombinant molecule research. It was thus only natural to 
continue to work with the K-12 strain during the development of 
biological containment systems. By using the lowest level of detect- 
ability possible with current techniques as the measure of permissable 
survival of a potential vector or cloning cell, the microbiologists 
worked toward the selection of vectors and host cells which would 
prevent any inadvertent survival or transmission of DNA recombinant 
molecules outside the research environment. The investigators 
engaged in the “construction” of such “weakened” variants then 
must provide data which demonstrates that the proposed vector and/or 
cloning cell meet the criteria for use of a particular kind of research. 
Dr. Curtiss expressed his opinion that when the proper combination of 
biological containment and physical containment are utilized, there 
should be essentially no hazard under the types of experiments per- 
mitted by the guidelines. He did caution, however, that the human 
factor is always involved in such experiments; thus there is a contin- 
uing need to insure appropriate training of individuals engaged in such 
research in order to minimize any potential error. 
D. The NIH Guidelines for DNA Recombinant Molecule 
Research 
Dr. Fredrickson 
Donald Fredrickson’s (Director of the National Institutes of Health, 
DHEW) testimony was primarily a summary of the current status of 
the NIH DNA Recombinant Research Guidelines. As Dr. Fredrickson 
pointed out, compliance with the guidelines is now a reouirement for 
all research funded by NIH. Because of the efforts of a special Federal 
Interagency Committee on DNA Recombinant Research, the Direc- 
tor indicated that all other Federal agencies who might fund similar 
research would also require compliance with the guidelines. Dr. Fred- 
rickson noted that he was very aware of the need for careful public 
as well as scientific consideration of the Federal actions with regard 
to regulating this type of research and summarized a number of steps 
which had been taken by his office to provide for public involvement 
in the development of the guidelines as well as other actions being 
taken at NIH. 
The NIH has established a Recombinant DNA Molecule Program 
Advisory Committee which reviews the guidelines and provides rec- 
ommendations to the Director for needed changes. Tnis Advisory 
Committee also serves to review proposals for the approval of vectors 
21 - 754—7 
5 
[Appendix B — 72] 
