London, June 27 (IANS) Britain is wary about a genetically modified (GM) version of the popular salmon fish, developed by the Americans, saying the fish designed to grow at twice the normal rate may have lost its nutritional benefits and could pose a danger to the wild salmon in its seas.

An American company, AquaBounty, has developed the fish which contains new genetic components that increase the production of the growth hormone, reducing the gap between farming the fish and making it ready for the market from three years to 18 months.

If the fish – named AquAdvantage salmon – gets approval from the food directorate, it will become the first GM animal approved for human consumption.

The GM salmon will be grown in fish farms but will be bred sterile to prevent them from getting into the wild and breeding with native salmon populations.

The salmon would need EU approval before it could be farmed in or imported to Britain. The EU has approved only two GM products for cultivation since 1998, a potato engineered for starch production and an insect-resistant maize.

An official of Britain’s Soil Association told The Sunday Times: ‘Once you have bombarded an animal with other genes, the DNA is unstable, and there is no guarantee these fish will remain sterile. It poses far too great a risk to wild salmon. A fish that grows so quickly is likely to lose some of the nutritional benefits.

‘There is no such thing as a free salmon lunch and we will pay the price.’

AquaBounty, however, said in a statement: ‘The product is stable and unchanged over multiple generations.’ It says approval for the fish would reduce the environmental impact of fish farms.

The salmon are an amazing fish with a unique history. They live in the sea but reproduce in fresh water. They live in fresh water during their early life, mature in salt water, and then return to fresh water to breed and then die. Some salmon migrate thousands of miles in the sea. They then return to the place where they hatched and continue the cycle. No one knows how salmon return home. On their journey home, they do not eat at all, they often change colour, their muscles soften, and they die soon after spawning.

The newly-emerged salmon are called alevins. When they grow a bit they are called the fry. As the fry mature, they are called parr. When it becomes silver-coloured, it is called a smolt. After growing for a while, the smolts swim downstream to the sea.

For every 8,000 eggs produced, 4,500 alevin survive, from which 650 fry survive, from which 200 parr survive, from which 50 smolt survive, from which only 2 spawning adults survive (who produce thousands of eggs).

(Venkata Vemuri can be contacted at venkata.v@ians.in)