The study was conducted at the Memorial University of Newfoundland, on Canada’s eastern seaboard.

Graduate student Darek Moreau says he and other researchers worked with what are called growth hormone transgenic Atlantic salmon. Those have an added Chinook, or king salmon gene, that speeds their growth.

Moreau says modified males were exposed to male and female wild salmon in a laboratory simulation of natural spawning conditions.

"So we basically put these fish together and allowed them to do what they do that time of the year and recorded the results. ... We found the transgenics had a much reduced breeding performance but they did, in fact, show an interest in breeding and the ability to breed," Moreau says.

The research, published in the scientific journal Evolutionary Applications, is the first to show this type of genetically engineered salmon can interbreed with wild fish.

Moreau says the study should raise concerns about the possible release of modified salmon through accidents at fish farms.

"If there was a significant number of escapes that occurred in succession over many years, there’s certainly the potential for there to be some harm," Moreau says.

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