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Animals aren't drugs

The US Food and Drug Administration is misguided in its approach to genetically modified animals.

It is more than 25 years since Ralph Brinster and Richard Palmiter first developed genetically engineered (GE) mice, proving that recombinant DNA techniques could be used to engineer animals.It has taken the US Food and Drug Administration (FDA) nearly as long to develop guidelines laying out its regulatory approach to such animals, be they intended as pets, as living drug factories or to supply American dinner tables.

In September, the FDA finally delivered its draft guidelines, effectively laying out a detailed playbook for companies seeking the agency's seal of approval to bring to market everything from fast-growing salmon to pigs with livers engineered for human transplant. The period for public comment on this important FDA document ends on 18 November (see

It is high time that the FDA stepped in to regulate this field, in which companies such as Aqua Bounty Technologies, a small Massachusetts enterprise that has engineered a salmon that grows to marketable adult weight in 18 months instead of 30, have been undermined by the agency's slowness to act. Agency involvement will, furthermore, bring needed regulatory oversight to an enterprise that, although often promising, could in individual instances go awry with unhappy and unpredictable consequences for the animals, public health and the environment.

But the agency's regulatory approach to the issue is troubling. It has used an eyebrow-raising reading of the 1938 Federal Food, Drug and Cosmetic Act to assert its regulatory authority over GE animals. The FDA says, in effect, that these animals meet the definition of a 'drug' under the law because they contain DNA that is “intended to affect the structure or function of the body.” Following from this, the guidance says that every new GE animal — with the notable exception of lab animals used in research — will be regulated as if it contains a new drug.

When a conventional drug is being assessed by the FDA, the existence and details of the application are protected under law from public scrutiny. Such protections are necessary in the highly competitive world of human pharmaceuticals. Applied to GE animals, they are much less appropriate. In essence, the agency is saying to the public 'trust us' — in the absence of evidence, for example, that it is adequately equipped to assess the potential environmental impacts of such animals. It is not just environmentalists who are raising the red flag; the National Research Council, in a 2002 report on animal biotechnology, listed “novel environmental issues” and the technological capacities of agencies like the FDA as among its “major concerns”.

It is understandable that the agency is trying to pour new wine into the 70-year-old wineskin of the federal drug law; the law is the only tool at its disposal for regulating GE animals. But as Henry Miller of the Hoover Institution at Stanford University, California, noted in a recent correspondence in Nature Biotechnology, “When the only tool you have is a hammer, more and more problems begin to look like nails.” (See

More light on the process than the FDA's proposal allows is needed to build public trust and to ensure that all necessary steps are taken to avoid adverse events. The current law cannot do this. Congress should step in and produce one that does.

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Animals aren't drugs. Nature 456, 2 (2008).

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