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A Food and Drug Administration policy published for public comment Sept.
18 threatens the health of a promising new field, the production of
animals with novel and valuable traits.
After more than 20 years of deliberation, the FDA's Center for
Veterinary Medicine has proposed that every "transgenic" animal crafted
with gene-splicing technology will be subject to the procedures and
regulations for drugs used to treat animal diseases, such as pain
relievers or anti-flea medicines.
But the introduction of a gene is not the same as the administration of
a drug. Moreover, the FDA's approach represents a major shift in the
regulation of biotechnology that will be hugely expensive to animal
breeders and detrimental to consumers.
What kinds of animals? One that has awaited an FDA policy for almost a
decade is an Atlantic salmon that contains a newly introduced Chinook
salmon growth hormone gene that remains turned on all year round
(instead of during only the warmer months, as in nature). This cuts the
time to marketable adult weight from 30 months to 18. The extra gene
confers no detectable differences in the salmon's appearance, taste or
nutritional value; it just grows faster.
There are numerous other applications in various stages of R&D,
including livestock with leaner muscle mass, enhanced resistance to
disease or improved use of dietary phosphorous to lessen the
environmental impacts of animal manure.
Until now, the FDA has not regulated new lines of farm animals or, for
that matter, animals used for what might be termed "medical purposes."
For example, they do not regulate German shepherds or golden retrievers
bred to enhance traits that make them better seeing-eye or companion
dogs. The FDA has not even asserted its jurisdiction over animals that
are "transgenic," or genetically engineered, for research, which include
hundreds of lines of rodents.
The "new drug" paradigm doesn't fit transgenic animals well. A better
model is the approach taken by another FDA component, the Center for
Food Safety and Nutrition, which places the burden of ensuring the
safety of foods and food ingredients on those who produce them.
The rules prohibit the adulteration (contamination) or misbranding
(mislabeling) of food, but the agency does not inspect or evaluate food
prior to its sale in shops, supermarkets or restaurants. Rather, federal
oversight relies on market surveillance, or post-marketing regulation,
and the FDA takes action if there is an apparent problem. This approach
has worked quite well over many years.
The law does require a pre-marketing safety review for certain
food-related products. These include most food additives - a class of
ingredients that includes preservatives, emulsifiers, spices, sweeteners
and natural and synthetic flavors or colors, among others. In general, a
food additive must be pre-approved if it becomes a component of or
otherwise affects the characteristics of a food and if it is "not
generally recognized as safe (GRAS) by qualified experts for its
intended use."
GRAS is an important concept: Before a new food additive is marketed, it
is the responsibility of the producer to determine whether or not the
substance is GRAS. The agency routinely reviews food additive
applications for safety only when the substance in question has been
determined not to be GRAS by the producer. If the producer determines
that a substance is GRAS, only a notification of that decision to the
FDA is necessary (which is then subject to agency review).
The FDA's existing approach to biotechnology and to foods in general
could be adapted easily to transgenic animals. Traditionally, the
combination of two GRAS substances is still GRAS. Similarly, because
adding a GRAS gene to a GRAS organism is likely to yield a GRAS outcome,
an FDA pre-marketing review would not be necessary for genetic
constructions like the fast-growing salmon. But instead the FDA intends
to treat every new animal as though it contains a "new drug," the
evaluation of which can take many years even if there is virtually no
likelihood of harm.
The FDA's approach to "novel" foods, published in 1992, is compatible
with the GRAS/food additive paradigm. It emphasizes that the Center for
Food Safety and Nutrition does not impose discriminatory regulation
based on the use of one technique or another, but that greater scrutiny
is applied only when certain safety issues are raised. These include the
presence of a completely new substance in the food supply, increase in
levels of a natural toxin, or the presence of an allergen where a
consumer would not expect it.
Officials at the FDA's Center for Veterinary Medicine say a newly
introduced gene expressed in an animal is analogous to the injection of
a new drug, that the genetic modification mediates the introduction of
the substance synthesized under the direction of the new gene - a
hormone or enzyme, for example. But this view ignores that neither the
FDA nor any other government agency routinely conducts pre-market review
of new genetic constructions that occur "naturally." (We call these
"mutants.")
An example is the Zucker rat, a naturally occurring mutant more than 4
times the size of its normal siblings, and which is available from
commercial breeders for research. Another more familiar example is the
mule, a horse-donkey genetic hybrid which, by any reasonable definition,
is certainly transgenic, although it doesn't involve the use of
newfangled genetic techniques.
Why would the FDA adopt such a dubious policy? Whenever they can,
bureaucrats exhibit a tendency to arrogate new responsibilities and
expand. "Dogs bark, cows moo, and regulators regulate," FDA Commissioner
Frank E. Young once quipped. And the "new drug" paradigm is the only
vehicle available to the Center for Veterinary Medicine. (Recall the old
adage, "When the only tool you have is a hammer, more and more problems
begin to look like nails.")
If animal biotech companies are to bring home the bacon, the FDA will
need to get its act together. When genetically engineered pigs can fly
Henry I. Miller, a physician and molecular biologist, is a fellow at
Stanford University's Hoover Institution. He headed the Food and Drug
Administration's Office of Biotechnology from 1989 to 1993 and is the
co-author, most recently, of "The Frankenfood Myth."
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