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OCR for page 69
Safety
Regulations
The clebate about the safety of recombinant DNA research began
almost as soon as the first such experiments were reported. In 1971 a
molecular biologist proposed to combine DNA from a monkey tumor
virus, known as SV40, with a plasmid from the bacteria Escherichia coli.
This immediately raised fears among some scientists that the modified
E. coli, containing monkey virus DNA, might somehow infect humans
and cause cancer. Though this possibility seemed unlikely, it could not
be dismissed for several reasons. First, E. cold commonly reside in the
human intestine. If the recombinant molecule were inadvertently in-
gested by a human, it might be able to establish itself in the intestine.
And second, though the virus has not been shown to cause cancer in
humans, it does cause cancer in mice and hamsters and also causes
human cells in culture to grow abnormally. After his colleagues voiced
such concerns, the molecular biologist voluntarily cleferred his experi-
ment.
When a small group of molecular biologists met at a Gordon Confer-
ence in 1973, they again discussed the potential hazards of recombinant
DNA experiments. After the meeting, they wrote a letter to Science to
alert the broader scientific community to their concerns. In the letter
they suggested that the National Academy of Sciences investigate the
hazard, which it did. in 1974 a National Academy of Sciences committee
recommended a worldwide moratorium on certain types of recombinant
DNA experiments—such as those that would introduce into bacteria
viral genes or genes that confer antibiotic resistance- until the safety
hazards could be assessed. They also called for an international confer-
ence on the issue and suggested that the National Institutes of Health
establish an advisory committee to develop safety guidelines for future
recombinant DNA research. All three suggestions were followed.
69
OCR for page 70
70
GENETIC ENGINEERING OF PLANTS
The conference was held the following year at the Asilomar Center
in Pacific Grove, California. By that time the scientists were not only
concerned about the cleliberate transfer into E. cold of a harmful gene,
such as a gene from a cancer virus or a toxin, but they also wondered
about the unforeseen hazards of combining genes of two different spe-
cies even if those genes were thought to be harmless. Since such
recombinant organisms clid not exist in nature, the scientists could not
predict with accuracy what risk they might pose, not only to human
health, but also to plants, animals, and the environment.
Nor was the debate confined to the scientific community. The public
became increasingly concerned about both the safety questions and the
moral and philosophical implications of the new technology. In creating
novel organisms, scientists would have the power to alter the course of
evolution. Many individuals, including some scientists, questioned
whether scientists should be entrusted with such power. They also asked
who should decide these issues the scientists or the public.
Yet at Asilomar, the discussion was focused on scientific issues. The
participants agreed that the moratorium should be liftect for the vast
majority of recombinant DNA experiments, provided that appropriate
precautions were taken. The safety strategy they suggested was that
recombinant microorganisms be contained and that the level of contain-
ment correspond to the level of estimated risk of each experiment.
Containment would be achieved through two methods: biological, the
i-
c'
use of enfeebled strains of bacteria that could not survive outside of the
laboratory; and physical, the use of laboratory procedures and equipment
to prevent inadvertent release.
A committee of the NIH, now known as the Recombinant DNA Ad-
visory Committee, or RAC, translated those recommendations into
guidelines. These guidelines, adopted in 1976, specify the physical and
biological containment conditions under which recombinant DNA ex-
periments can be performed.
The guidelines are binding only for federally funded research. To date,
ndustry has voluntarily complied with the guidelines, following pro-
cedures suggested in the guidelines for obtaining project approval.
In research conducted since 1979, the alleged hazards have not ma-
teriaTized. As knowledge accumulated, the guidelines have gradually
been relaxed that is, the containment levels required for certain ex-
periments have been lowered. Now most experiments can be performed
at the lowest biological and physical containment level.
Nonetheless, some safety questions still remain. One is the risk posed
by the intentional release of novel organisms into the environment.
Researchers have engineered microorganisms that, in the laboratory,
OCR for page 71
SAFETY REGULATIONS
71
can degrade a dioxin or others that might be used to clean up oil spills.
The major uncertainty is whether they will disrupt the balance of the
ecosystem in which they are released.
The concern is not with genetic engineering per se. The introduction
of any species to an ecosystem it does not normally inhabit can have
unexpected results. There are many examples of organisms that have
become serious pests after they were released into a new area. In IS69
the gypsy moth (Porthetria dispar) was introcluced into Massachusetts as
part of a silk production experiment. It is now a serious forest pest in
much of the Northeast. Prickley pear cactus (Opuntia) was introduced
into Australia from Latin America and posed a serious threat when it
spread into grazing land. The South American cactus moth (Cactoblastis
cactorum) was deliberately introcluced into Australia to bring the cactus
under control.
The Need for Continued Diligence
.
Ray Thornton was an active participant in much of the early debate
over recombinant DNA regulation both as a former U.S. congressman
anc} as chairman of the RAC from 1980 to 1982. He is now president of
Arkansas State University. As he described, he addressed another con-
vocation at the National Academy of Sciences seven years ago.
"As ~ stand here, ~ can't help but have a sense of deja vu. This room
was filled with people concerned about whether there should be a mor-
atorium on all recombinant DNA research. There were placards, there
were protesters, there was heckling from the audience. It took a good
bit of courage at that time to stand in this auditorium and suggest that
the needs of science called for us to move forward cautiously and care-
fully in this area. That has changed over the past seven years, and today
we recognize the enormous potential benefits that this new technology,
this new way of doing things has made possible.
"Perhaps it may also require a bit of courage to suggest to this group
today that there is still a continuing need to be aware of the safety,
ethical, and moral issues of genetic engineering."
Thornton remincled the audience that these technologies provide an
opportunity to direct the course of evolution, particularly to speed it.
On a practical level, such changes can disrupt an ecosystem. On a
philosophical level, this new ability may undermine man's reverence
for life.
Many researchers and observers of the field think that if scientific
work proceeds intelligently and prudently, and if scientific directions
and developments are open to public scrutiny, then the safety issues
OCR for page 72
72
GENETIC ENGINEERING OF PLANTS
can be resolved. Others, Thornton said, are less convinced that humanity
is prepared to cope with the moral and ethical aspects of genetic engi-
neering.
To ciate, scientists have been able to pursue recombinant DNA re-
search with remarkable freedom, Thornton said. The use of voluntary
guidelines—rather than legislation—is a novel approach and is far more
flexible than the regulations governing the atomic, pharmaceutical, and
chemical industries. He sees this freedom given to genetic engineering
as a reflection of the public's confidence in the scientific community; of
the public's belief that safety issues will be openly and honestly cTis-
cussed.
"Only a handful of serious safety questions remain for RAC to con-
sider," Thornton said. Among those is the release of genetically engi-
neered organisms into the environment. "We're not talking about work-
ing with new organisms in the laboratory. We're talking about what
recombinant life forms can be put in an oil well."
Other issues may emerge as the genetic engineering of plants nears
application. In deciding what, if any, regulatory approach to take, the
RAC or any other oversight bocly will need to draw on the knowledge
of agricultural scientists, ecologists, and others. "One of the things that
may have gone wrong six or seven years ago, that may have contributed
to the public outcry over recombinant DNA research, is that the mo-
lecular biologists who were involved did not have the benefit of input
from immunologists, epidemiologists, and others who couIcl have helped
them to assess the dangers. Because of this lack of knowledge, the
restrictions initially applied were perhaps too severe. We have an op-
portunity to learn from that mistake. By drawing on the expertise of a
number of disciplines, we can develop an approach that both satisfies
the concerns for safety, yet does not unduly restrict the application of
new research methocls."
Representative terms from entire chapter:
genetic engineering
