Genetically engineered salmon that grow ten times faster than normal fish have been swimming around in holding tanks in a British Columbia laboratory for the past few years, posing a scientific dilemma.

While the science has intriguing potential (who wouldn't rather catch a 20 lb. salmon than a 2 lber?) government researchers have recognized that the altered fish could pose an environmental threat if they ever got out into nature.

“There are a lot of regulatory issues that need to be addressed,” Mr. Devlin said in an interview, before listing the problems his souped-up fish might create. Chief among them is concern that the “transgenic” salmon will pass on their altered genes to wild fish if they ever get loose.

"We will not be transferring our fish out of the lab," he states. "Ours are for research only. For risk assessment purposes."

Why fool with something that could be dangerous?

"We need living model systems to allow us to acquire objective data, rather than speculation about the benefits and risks of transgenics," argues Mr. Devlin.

The genetically altered fish are not quite as spectacular as a Scottish sheep that made headlines a few years ago, when it was successfully cloned from one of it’s mother's mammary cells. But the fish pose a more pressing problem for policy makers. Even if the government decides not to exploit Mr. Devlin’s superfish, other researchers are keen to put genetically altered fish to work in aquaculture.

A/F Protein Inc., set up by Newfoundland geneticist Garth Fletcher, has already created a fast-growing Atlantic salmon, which the company has been testing in a Scottish hatchery. According a report on Mr. Fletcher’s“money-making giants” in New Scientist, a British publication, the salmon grow 10 times faster than normal, just as the Canadian fish do.

A/F Protein, which has recently expanded it’s fish engineering business into Prince Edward Island, is also trying to insert anti-freeze genes into salmon to make them more cold tolerant.

“The goal is definitely to use them (A/F Protein's genetically altered fish) in aquaculture,” says Mr. Devlin, who along with creating transgenic fish is helping the federal government devise regulations to control their use.

He says more work is needed on how to contain the fish through better rearing and sterilization techniques.

It’s unlikely the altered fish would survive long in the environment, since they do not swim as well as wild fish, Mr. Devlin says. But it's possible genetically reprogrammed fish with their “voracious appetites” might thrive in some areas, reproduce and start out competing wild fish.

“We are unable to predict the impacts at this stage, ” says Mr. Devlin, whose team has found the transgenic fish can out-compete wild fish for food in lab trials.

Some genetically engineered Atlantics have been raised in a fish farm in New Zealand, but the company put a stop to the project earlier this year when concerns were raised about deformed salmon.

Mr. Devlin doesn't expect to see transgenic fish allowed in sea pens anytime soon in North America, since they are sure to escape.

The fish farming industry has been plagued with escape problems everywhere, and in British Columbia biologists have proof they have entered rivers and may have successfully spawned.

“If we grow them in net pens we can assume that fish will eventually escape,” says Mr. Devlin.

It’s more likely that genetically engineered fish will be allowed only in land-based facilities, says Mr. Devlin, who is also pushing for “complete biological containment” of the fish through sterilization. The most promising technique involves pressure-shocking fish eggs. It’s 100 per cent effective at sterilizing fish in the lab but it’s only 99 per cent effective in large trials.

“It’s good but it’s not perfect,” says Mr. Devlin, stressing the need to be extra cautious with the fish.

“Once they get loose there is no way to get them back,” he warns.

He and his colleagues have been creating transgenic fish for several years as part of a government effort to understand a wave of new fish technologies emerging to meet the growing world demand for fish products.

A few years ago Mr. Devlin’s team engineered several variety of salmon that grew 10 times faster than normal. The extraordinary growth led to abnormalities in some of the fish, such as excess cartilage in the head area.

“It was clear we needed to back off with the growth simulation,” says Devlin. They’ve now created 20 new genetic lines of salmon, which they expect will only grow five to seven times faster than usual and look normal.

Several thousand fish - hundreds of each new line - are in holding tanks in the lab, weighing about a kilogram each.

“They’re doing very well,” says Mr. Devlin.

The federal government has filed a patent application on the technique for creating transgenic fish.

"This has been done to ensure that we can control and prevent use of our findings by others, rather than to control any profit from them," says Mr. Devlin.

The fish are created by injecting fish eggs with a micro-droplet of a potent sequence of genes. The sequence, which Mr. Devlin and his associates stitched together using genes extracted from other fish, incorporates itself into the genetic material in the fish eggs at different spots.

“Once it’s micro-injected into the eggs it’s out of our hands,” he says, referring to the way transgenic fish have different growth rates depending on where the inserted genes landed.

When the scientists come up with a transgenic fish they like, they can generate more by harvesting sperm and eggs from the fish. The transgenic fish pass on the new genes on to their offspring.

While the fish can have spectacular growth rates, Mr. Devlin says he doesn’t think he and his colleagues are improving on nature.

“A great looking fish in the lab might have all sorts of problems in the field,” he says. He also says it’s unlikely their huge appetites could be met in the wild.

“Transgenics need twice to three times as much food to survive and that probably isn’t out there at certain times of the years,” he says.