March 1, 2007

Modified salmons less dangerous to wild species than expected

A new study suggests that salmon genetically modified to grow 25 times larger than wild ones would be far smaller if it actually enters the wild.

The report, by the Center for Aquaculture and Environmental Research in Vancouver, Canada was published in the Proceedings of the National Academy of Sciences. The research looked at transgenic coho salmon which is modified to make extra growth hormones.

Modified salmon were able to grow up to 25 times the size of normal coho when raised in a hatchery.

One main concern was that if these salmon escaped into the wild they would compete with wild salmon for food in order to achieve their sheer sizes.

However, under simulated natural environments, Coho grew to just twice the size of their wild cousins and ate less prey than those grown in hatcheries, the research said.

Despite the findings, researchers say it is too early to know whether such salmon are safe to be let out of the lab so there are no ways of verifying whether they could reach their full potential in the wild. The researchers also warned that the simulated environment created in the lab would not fully resemble conditions in the wild.

Still, some scientists said the study shows, to a limited extent, that the threat of modified salmon is not as big as previously thought.

Although species such as salmon, tilapia, and other fish have been engineered to grow faster and bigger, no transgenic fish has been approved for commercial farming in the United States.

Environmental concerns such as genes of escaped fish mixing with the genes of wild species continue to prompt concerns about transgenic fishes.