The federal review process for genetically engineered food animals, now being applied to fast-growing salmon, is tortuously drawn out, scientifically unjustified, and likely to rob society of both environmental and economic benefits, argue researchers at the University of California, Davis, and Purdue University.

In a commentary piece published today (Aug. 5) in the online version of Nature Biotechnology, animal scientists Alison L. Van Eenennaam of UC Davis and William M. Muir of Purdue University recap the regulatory review saga of AquAdvantage salmon, a fast-growing genetically engineered salmon. (The article is available here.)

“Although the first genetically engineered animals were developed almost 30 years ago, none has been approved for food production,” said Van Eenennaam, a Cooperative Extension animal genomics and biotechnology specialist in UC Davis’ Department of Animal Science.

“The protracted evaluation of the AquAdvantage salmon, and continuing uncertainties in the regulatory process and timeline, have essentially halted commercial investment in the development of genetically engineered animals for agricultural applications in the United States,” said Van Eenennaam, who served on the U.S. Food and Drug Administration’s Veterinary Medicine Advisory Committee, which was charged with reviewing a proposal to commercialize the AquAdvantage salmon.

The AquAdvantage salmon, developed by Aqua Bounty Technologies, carries a gene from Chinook salmon that speeds growth and improves feed efficiency in farm-raised fish. The fast-growing, genetically engineered salmon has been under federal regulatory review by the FDA since 1995.

Opponents of the genetically engineered salmon have expressed concerns that the new fish might force the wild salmon population into extinction if they were to make their way into the wild, and could pose an increased allergy risk for consumers. Muir and Van Eenennaam counter that neither concern is substantiated by scientific data.

The authors point out that AquAdvantage salmon would be raised in fully contained, land-based facilities, precluding their interaction with wild salmon populations. Further, data suggest that the fast-growing salmon are less fit than their native counterparts and would not be able to compete in the wild. The authors note that the availability of the genetically engineered fish could, in fact, help reduce fishing pressure on wild salmon populations.

As for allergenicity concerns, Muir and Van Eenennaam contend that there are no data to support the claim that the genetically engineered salmon carry substantially more allergens than nongenetically engineered salmon. They also maintain that many fish consumed regularly, such as herring, are potentially more allergenic than either conventionally bred or AquAdvantage salmon.

The FDA concluded that AquAdvantage salmon were safe to eat and were not expected to have a significant environmental impact, given the proposed containment measures. But critics continue to charge that the regulatory agency has not adequately addressed their concerns, and have mounted political efforts to block the final approval necessary before the fish can be commercialized.

Muir and Van Eenennaam support the FDA’s science-based evaluation of the AquAdvantage salmon, and call for the agency to monitor the genetically engineered fish as they are raised commercially in captivity to check for any future problems. The researchers maintain that the lengthy review process — now in its 16th year for the AquAdvantage salmon — is uncalled for, especially given that similar review is not required for food animals with traits developed through conventional breeding.

"We realize that any new technology can have risks, and those risks need to be assessed in a thorough and convincing manner," Muir said. "However, once the assessment has been completed and the agency concludes from the weight of evidence that risks of harm, either to the environment or to consumers, is negligible, the next step, which is to allow production and sale of the product, needs to be taken."

In their commentary piece, both researchers state that they have no competing financial interests related to the genetically engineered salmon issue.