7 
as an inhibitor to the production of glucagon and insulin and to the 
pituitary gland’s release of hormones regulating body growth. 
Roy Curtiss of the University of Alabama noted in his testimony 
that modification of the microorganism so that gene expression occurs 
is only the first of several difficulties that will be encountered in pro- 
ducing hormones commercially. 
Second will be to prevent tbe microorganisms from degrading proteins which 
are nonfunctional, and the presence of a hormone would seem to be in that 
category. Third will be to allow the microbial host to secrete the hormone inro 
the culture medium to facilitate its recovery, free from bacterial contamination. 
Fourth, in addition to these essential modifications of the microbial host-vector 
system, it would be highly desirable to have the microorganism adapted for use 
in fermentation technology and thus grow on an inexpensive medium with 
maximum yields of hormone and minimum yields of microbial cell mass. 
Nevertheless, Ronald Cape, president of Cetus Corp. of California, 
suggested that some nonmedical products could be available in a year 
or two if there are adequate markets for them. 
Other applications 
More speculative uses of recombinant DNA include the release of 
the modified host cell into the environment for some specific purpose 
such as the conversion of organic material in sewage treatment, the oxi- 
dation of petroleum spills, or improvement in the nitrogen-fixing 
capability of plants. In all of these examples the intention -would be 
to establish the recombinant organisms in a natural environment as 
substitutes for organisms which perform the same functions but less 
efficiently. Alternatively, it has been suggested that a modified vector, 
probably a virus, could be used to infect plants or animals in order 
to increase the photosynthetic capability of plants, destroy insect 
pests, or produce some other desired genetic change. The most dra- 
matic example would be the injection into human beings of a virus 
capable of correcting disease-causing genetic defects. 
Service industry 
If research and development with recombinant DNA progress as 
the subcommittee’s witnesses expect, it may become profitable for 
commercial firms to supply specialized products to academic and com- 
mercial laboratories. These include not only restriction enzymes but 
also selected or general DNA segments, vectors with precise specifica- 
tions, and even organisms containing recombinant DNA. Such mate- 
rial is already routinely exchanged among research laboratories. More 
than likely, the volume of shipments would not be large, for the naked 
DNA would be inserted into a small number of vectors, the vectors 
incorporated into microorganisms, and the organisms propagated in 
quantity in the research or industrial laboratory. 
Potential Hazards 
GENERAL CONCERNS 
The ability to transfer genetic information across biological bar- 
riers previously considered to be blocked has raised three distinct con- 
cerns: first, that some new pathogenic microorganism might be cre- 
ated, escape from the laboratory, and prove dangerous to man or the 
23-S90 — 7S 2 
[Appendix B — 267] 
