Make Way for Frankenfish!

By Frederic Golden

Whether served as raw sushi, grilled steak or in thin smoked slices, most of the salmon you eat these days is not the sleek sport fish that has been a favorite of anglers since Izaak Walton but rather a chunky, sluggish creature raised in captivity. Indeed, salmon caught in the wild accounts for less than half of all salmon sold in the U.S.

Now gene splicers have cooked up a replacement that sounds like a fish tale: a veritable superfish, one that can grow at least twice as fast, resist disease and outmate competitors. If approved, it could provide protein to millions of people at a time when fish stocks are perilously low. But as you might expect, some critics are carping. They consider the supersalmon a biological time bomb that could destroy the remaining natural salmon populations and wreak other environmental havoc. To them, the supersalmon is nothing less than a "Frankenfish."

Unlike other genetically modified foods--so-called Frankenfoods--the supersalmon was born almost accidentally. About 20 years ago, a fish researcher in Newfoundland found that even though his saltwater tank had frozen, the flounder in it survived. Adapted to icy Canadian waters, the fish turned out to have a gene, known in other polar fishes, that produces an anti-freeze protein. While trying to splice this gene into salmon so it too could be grown in colder waters, scientists made a second accidental discovery: they found that while the gene didn't keep the salmon from freezing, a portion of it, when stitched onto a salmon's growth-hormone gene, greatly speeded development--up to five or six times as fast as in the early months and about twice as fast overall. Patenting their discovery, the scientists started a company in Waltham, Mass., called A/F Protein (A/F stands for antifreeze).

The company has 10,000 to 20,000 Atlantic supersalmon swimming in endless circles in 136 tanks at three locations in Canada's Maritime provinces. The hope is that these fish will soon be producing eggs for commercial aquaculture not just in Canada but in New Zealand, Chile and the U.S. as well. By turning to the supersalmon, says Elliot Entis, A/F's president, fish farmers could double production without doubling costs because the fish converts food into body mass so much more efficiently than ordinary salmon. That, he says, would mean "more fish for more people at a lower price."

But this so-called blue revolution may not reach U.S. shores for a while. Although gene scientists in the U.S. have been tinkering with a variety of marine creatures--not only salmon and trout but also carp, catfish, tilapia and shrimp--these efforts are drawing criticism similar to that directed at genetically modified foods. Opponents, who complain about the fertilizers and other pollutants released into coastal waters by the fish farms, are especially concerned about the potential impact on the gene pool. They note that domesticated fish regularly escape from their pens into the wild and breed with native stocks, upsetting the balance of nature.

No one knows what ripple effects might occur if the new supersalmon escaped into the wild. One of the few studies done by U.S. researchers found a lower survival rate for eggs produced by transgenic fish. Still other studies show that despite their name, so-called superfish have diminished muscle structure and swimming performance. Says Canadian fish geneticist Robert Devlin: "Science, at the moment, is unable to give us a reliable assessment of risk."

Entis and others reply that whatever the risk, it could be lowered to almost zero by raising the fish in closed tanks rather than in storm-exposed pens. Still another tactic under consideration is shocking the fertilized eggs so they create fish that cannot reproduce--a marine equivalent of the self-destructing terminator gene that Monsanto once considered putting in its patented plant seeds.

Fearing a consumer backlash, New Zealand King Salmon, a major producer of Chinook salmon--the largest Pacific salmon--announced last week that it was suspending its gene-modification experiments. Entis, by contrast, believes he can win acceptance of his supersalmon through public education. "We have to show we have nothing to hide," he says.

But don't count on putting supersalmon lox on your Sunday-morning bagel anytime soon. The Food and Drug Administration must first approve introduction of the fish into the U.S., something that probably won't happen before 2001.

--Reported by Dick Thompson/Washington

With reporting by Dick Thompson/Washington