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The Creepy Science Behind Genetically Engineered "Frankenfish" About to Enter Our Food Supply Unlabeled

This salmon would be the first genetically engineered animal to enter the U.S. food supply, and the science behind its approval process is frightening.

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AquaBounty tested its GE salmon and controls for physical and behavioral problems, differences in blood test results and hormone levels, and allergenicity to humans. Although the commercialized fish will all be female triploids, they often tested both males and females and both diploids and triploids of non-GE and GE salmon to determine whether any problem that showed up was due to the genetic engineering or due to the extra set of chromosomes.

However, in many of the tests, AquaBounty used sample sizes as low as six fish, much less than the minimum of 30 needed for the results to have statistical significance. Hansen said a small sample size might make sense if the animals were elephants, but there is no reason why AquaBounty should not have tested more fish. Moreover, in one of the tests, the six fish in each study group were selected from larger groups of 100 to 200 fish, and the report did not specify that they were chosen randomly. Additionally, AquaBounty admitted to culling deformed fish prior to selecting fish for inclusion in its studies. The company justified this by saying that culling is standard practice in the industry. That may be so, but for the purpose of comparing deformities between GE and non-GE salmon, the culling and sampling practices reduce the reliability of the results.

Another alarming practice -- one Hansen felt qualifies as misleading -- was AquaBounty's reliance on 2007 data (the best year for the GE fish and simultaneously the worst year for non-GE fish) and its characterization of 2005 data (the worst year for the GE fish) as an outlier to be ignored. By using 2007 data for many of its studies, AquaBounty was able to compare its best group of both diploid and triploid GE salmon against the group of non-GE salmon with the highest frequency of physical deformities (compared to each of the other years of testing, 2003-2006).

On the other hand, in 2005, the GE fish exhibited an unusually high frequency of physical deformities (only 7.9 percent of triploid GE salmon and 17.2 percent of diploid GE salmon were judged to be free of any malformations), and AquaBounty provided several justifications for ignoring this data, suggesting that perhaps the small sample size (38 fish) of GE triploids was to blame. Hansen says if that were true, we would not also see such poor results in the diploid GE fish, which had a sample size of over 1,500 salmon.

The problem could have been environmental, offered AquaBounty. Maybe the problems were caused by nutrient deficiencies, exposure to antibiotics, contaminants in feed, parasites, or water temperature. Yet, if that were the case, notes Hansen, we would also see a high rate of malformations in non-GE fish in 2005, and we do not. Both the diploid and triploid groups of non-GE fish performed well in 2005, with 98.7 percent and 89.0 percent showing no malformations, respectively. Hansen also dismissed AquaBounty's assertion that the extra chromosomes in the triploid salmon were responsible for the 2005 data, as both the diploid and triploid GE salmon performed poorly, but the non-GE triploids performed quite well.

Despite the problems noted above, the FDA concludes from the data that, "Analyses of the behavior and gross external abnormalities of market size (1,000-1,500 g) AquAdvantage Salmon show no demonstrable differences from the comparator fish population." One last flaw Hansen points out is the study's examination only of adult fish, and not of fish in all life stages, beginning with the egg. The FDA, perhaps worried about this, and certainly worried about AquaBounty's heavy culling of fish in early life stages (not to mention their lack of data on fish that were culled), called for a Durability Plan that includes "monitoring, data collection, and reporting of abnormalities observed under commercial production and grow-out conditions at the Panama facility where AquAdvantage Salmon will be reared" after the fish are approved and commercialized. Hansen feels this is insufficient, comparing it to allowing the fox to guard the henhouse and report if any chickens are being eaten.

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