BONN, Germany (CN) - Genetic "bar-coding" may be on the horizon in a global effort to stop the mislabeling of fish. Just as universal product codes, or UPCs, are scanned at the grocery checkout line, soon it may be possible for inspectors to determine the species of fish using handheld scanners.
With fishing on the rise globally and most fish stocks fully or over-exploited, government regulators are becoming preoccupied with illegal, unregulated and underreported fishing. Around one-third of the fish consumed in the United States is mislabeled, while the European Commission says imports of unscrupulously caught fish could add up to $1.6 billion per year.
The U.S. Food and Drug Administration has been studying whether to move from traditional methods of fish identification, which include analyzing their physical features and proteins, to the DNA bar-coding approach. Meanwhile, a recent European Union report reviewing scientific methods to combat illegal fishing outlines some of the steps required for implementing genetic bar-coding technology.
Scanning for Species
DNA bar-coding represents a technological advance from traditional morphology or protein-analysis methods, since it includes the ability to use even tiny samples from all developmental stages of fish. Processed fish, such as what one finds in a can of tuna, can also be identified using DNA bar-coding - a major advantage over older methods.
As opposed to DNA "fingerprinting," which analyzes the genetic code of an individual, DNA bar-coding is used to identify members within a species. It involves analyzing a specific portion from the genome, such as the cytochrome c oxidase, or CC1, subunit. This gene is well suited for bar-coding, as it is evolutionarily stable and consistent across a species.
The CC1 region of the mitochondrion - a molecule that comprises part of cells - consists of 648 of the billions of base pairs that make up DNA for complex organisms. Graphically, it could be portrayed as a barcode of black stripes of difference widths. Using scanners, nonscientists could match this image with existing codes in a database, thereby determining to which species a specific organism - for example a fish on a boat - belongs.
One proponent of such a future is the Fish Barcode of Life Initiative, a project that set out to create a standardized global library of fish barcode sequences. So far, about 8,300 of the 35,000 fish species worldwide have been coded.
The fish database is part of a greater project by the Consortium for the Barcoding of Life, based in Washington D.C., which proposes to use the CC1 as a standard for barcoding other animals. Scientists in the United States, Japan and Europe have apparently agreed to the consortium's data standards in populating an international genetic bar-code database.
Barcoding of Life's fish project isn't the only genetic database developed for aquatic species, but it is perhaps the one that has generated the most momentum to date. Such a project is even possible because of technological advances in the field of genetics, which have reduced the costs associated with genetic analysis.
A 2008 study brought the Barcoding of Life database into play for fish analysis. Scientists at the University of Guelph in Ontario, Canada, working with the Barcoding of Life project analyzed 96 samples of fish obtained at markets and restaurants in Canada and the United States.
Of the 91 samples they were able to analyze, 23 were mislabeled in some way. The most mislabeled fish was red snapper, with seven out of nine samples having nothing to do with the species. This research upholds other studies indicating that 75 percent of all red snapper sold in the United States is mislabeled.
And "white tuna" from sushi was really tilapia - among the cheapest of all farmed fish.
Aside from affecting consumers' pocketbooks, such mislabeling also has environmental implications. Atlantic halibut, from a collapsed stock, was subtly mislabeled as "Alaskan halibut," an eco-friendly alternative.
The European Union passed regulations, which came into force last year, to control fish "from ocean to fork."
A recent EU report emphasizes the importance of traceability. It says research needs to be better transposed into practical applications, also underlining the need for standardized data and better access to it.
By some estimates, inspectors could be boarding boats with portable genetic scanners in just five short years.
Since regulation tends to move slower than technology, however, it still remains to be seen how long it will take for this to hinder illegal fishing and whether new regulation will be too late for the fish.
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