In the 1990s, the U.S. Food and Drug Administration (FDA) used proteins to identify seafood, but the profiling method could only match to a standard sample. They had to have frozen tissues from all of the species they wanted to compare and the agency did have a collection to work with, but no matter how well you store the fish used as standards, their proteins tend to break down after about 10 years, so FDA began to lose the ability to identify seafood species in 2000. At the end of June, the U.S. Department of Health and Human Services awarded one of its seven 2015 innovation awards to FDA’s Fish SCALE (Seafood Compliance and Labeling Enforcement) project for transitioning the agency toward new DNA barcoding. The patterns in DNA don’t change. “So now, instead of a frozen tissue standard, all you have is that reference sequence, which can be attached to an email,” says Jonathan Deeds, principal investigator for Fish SCALE. project got its start, in part, thanks to puffer fish. Puffer fish can potentially be toxic, and only one species is allowed into the U.S. Any other type of imported puffer fish is subject to a standing import alert — a notification to FDA field staff that shipments of an imported product may be refused admission without physical examination. There were some suspect cases of illness connected to puffer fish in 2007, and FDA really needed to confirm whether it was the allowed species or not. Since none of FDA’s labs were running protein-based species identification by that time, they turned to a group at the University of Guelph — now called the Canadian Centre for DNA Barcoding — for help. Afterward, Deeds says the team realized “this technique works really well. We should really replace the old protein method and reestablish this method across the agency.” The FDA team collaborated with Guelph and the Smithsonian’s Laboratories of Analytical Biology to standardize, validate, and publish a protocol for DNA barcoding for fish species. They then implemented it throughout the agency so that nine of FDA’s field laboratories across the country now use the identification method. For crustaceans, they’ve finished the method and validation paper but are still in the process of getting it published. Once that happens, it will also be transferred out to the labs. Fish SCALE has also curated reference libraries of DNA sequences for commercial fish, shrimp, crab and lobster species, with classification help from the Smithsonian and Darryl Felder at the University of Louisiana at Lafayette. The public online library has more than 1,000 sequences on it, but FDA will just keep adding to it as they get samples. “We’re going to be building these for a long time,” Deeds says. “There are 30,000 species of fish in the world, and that’s just fish. It’s that, or more, when you hit shrimp, crab and lobster.” FishSCALE_406x250One of the advantages of DNA over the old protein method, which just gave you a yes-or-no answer to the match, is that even if the exact species match is not in the library of sequences, it will group with close related species. “Very often, we still have enough information to determine that it was a grouper or a snapper,” Deeds says. Fish SCALE uses species identification anytime there’s an illness, or if there’s a complaint from a consumer or industry. “We’re doing those all the time as they come up,” Deeds says. More than 90 percent of seafood in the U.S. market is imported, and there has been increased concern in recent years about seafood fraud — misrepresenting or mischaracterizing seafood in the supply chain (including species substitution) for economic gain. The practice can lead to illnesses caused by allergens, natural toxins, or other hazards. In response to some of the concerns about seafood fraud raised by the Government Accountability Office, the media and advocacy groups, Fish SCALE also conducted three sampling assignments for broad-scale surveillance of fraud in certain species at import and wholesale. “Whenever we find mislabeling on an imported product, the firm is placed on import alert,” Deeds says. “Since we’ve done this testing, there’s been at least 12 firms added to that red list.” Fish SCALE’s work over the past seven years was honored with a 2015 HHS Innovates Awards. Deeds says that although he and six other FDA employees were listed as the key contributors on the award, it was the involvement of dozens of people both inside and outside of the agency that have helped make it a success. “It wasn’t just a research effort,” Deeds says. “It was taking research and transferring it across FDA and using it in compliance programs, using it to make regulatory decisions.”

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