While the debate over whether to label foods containing GMO ingredients plays out across the country, another engineered food has long been waiting to hit grocery stores: genetically modified salmon.
While the debate over whether to label foods containing GMO ingredients plays out across the country, another engineered food has long been waiting to hit grocery stores: genetically modified salmon.
Produced by Massachusetts-based biotech firm AquaBounty Technologies, the fish is an Atlantic salmon engineered to grow twice as fast as its conventional, farm-raised counterpart. But AquaBounty's fish has been languishing in the regulatory process: The company has been trying to get the U.S. Food and Drug Administration to approve its salmon for sale for nearly 20 years.
One concern repeatedly raised by critics who don't want the FDA to give the transgenic fish the green light: What would happen if these fish got out of the land-based facilities where they're grown and escaped into the wild? Would genetically modified salmon push out their wild counterparts or permanently alter habitat? In a review paper published this month in the journal BioScience, scientists tackle that very question.
Robert H. Devlin, a scientist at Fisheries and Oceans Canada, led a team that reviewed more than 80 studies analyzing growth, behavior and other trait differences between genetically modified and unaltered fish. The scientists used this to predict what might happen if fish with modified traits were unleashed in nature.
Genetically modified salmon contain the growth hormone gene from one fish, combined with the promoter of an antifreeze gene from another. This combination both increases and speeds up growth, so the salmon reach a larger size faster.
Altering a fish's genes also changes other traits, the review found. Genetically modified salmon eat more food, spend more time near the surface of the water, and don't tend to associate in groups. They develop at a dramatically faster rate, and their immune function is reduced.
But would these altered traits help genetically modified salmon outcompete wild salmon, while at the same time making them less likely to thrive in nature? It's unclear, says Fredrik Sundström, one of the study authors and an ecologist at Uppsala University in Sweden. He stresses that we can't assume genetically modified fish would perish quickly in nature, just because they didn't evolve there.
It's analogous, he says, to invasive species. "Invasive species also didn't evolve in the environment where they are now invading, and they still are able to survive and flourish. We could argue along the same lines with the [genetically modified] fish."
Despite obvious differences between genetically engineered and wild salmon, predicting what could happen in a real escape is challenging.
Continue reading at NPR.
Salmon image via Shuttestock.
