[THS] A giant leap into the unknown: GM salmon that grows and grows
The Harder Stuff in news and commentary
ths at psalience.org
Sat Oct 2 13:08:59 CEST 2010
A giant leap into the unknown: GM salmon that grows and grows
A landmark in genetic modification is provoking fierce reactions
By Steve Connor, Science Editor
Wednesday, 22 September 2010
A genetically modified salmon, back, and a normal salmon of the same age
Its many detractors have called it the "Frankenfish". They say it will leave poison on
our dinner plates and spoil the marine environment. Its proponents, meanwhile,
argue that a genetically modified salmon could help preserve the oceans and feed
the world for decades to come.
The GM Atlantic salmon grows twice as fast as its wild cousin. Its genes have been
artificially augmented with DNA taken from two other fish the Pacific Chinook
salmon and an eel-like species called an ocean pout (Zoarces americanus) in order
to boost the growth hormone that allows it continually to put on weight throughout
After two decades of research and development, and almost as many years of
legislative wrangling, the company behind the GM salmon believes that it now stands
on the verge of an historic decision by the powerful US Food and Drug Administration
(FDA) that will open the way to the sale of genetically engineered meat and fish both
in the United States and the rest of the world.
Yesterday, the FDA held a public consultation on the sort of labelling the GM salmon
should be given, following an exhaustive scientific review which found there were few
serious concerns about the risk either to human health or to the natural environment.
A spokeswoman for the administration said a final decision on whether to approve the
sale of the GM salmon eggs can now go ahead. "There is no timeline on a decision
on the application, but I would predict it more along the lines of months, rather than
weeks," she told The Independent.
The Massachusetts company AquaBounty Technologies believes it has done
everything possible to show that farmed GM salmon will be both safe for humans to
eat as well as being harmless to the marine environment although this had done
little to quell the concerns of its detractors.
There is little risk of the GM salmon escaping to the wild, because they are designed
to be grown in fish-farm tanks on land rather than in pens out at sea. Even if they do
escape, the fish will not interbreed with wild salmon because the GM eggs have been
designed to develop into sterile females, said Ron Stotish, AquaBounty's chief
But there is already fierce opposition to the principle of GM salmon from consumer
groups, animal welfare organisations and environmentalists. A coalition of 31 such
groups in the US has stated their implacable opposition to a product they believe is
potentially dangerous to human health and the environment, as well as cruel and
painful for the GM fish, which they say are created to grow unnaturally fast.
If the FDA gives its approval, which many commentators believe is now inevitable
given that its scientists have found little to argue against doing so, the opponents of
the GM salmon insist that it should at least be clearly labelled as a product of genetic
engineering. "It is essential to label a genetically engineered animal so that any
unexpected effects will be recognised and consumer health protected," said Michael
Hansen, a senior scientist at the US Consumers Union, who disagrees with the FDA's
ruling that genetic engineering in itself does not constitute a material difference
between the GM fish and its wild counterpart.
The FDA's own scientific evaluation, however, is that the modified genes inserted into
the GM salmon are unlikely to give rise to any adverse effects to human health, either
directly from toxic effects such as allergic reactions, or indirectly from metabolic by-
products of the genetic modification.
In the US, the FDA has already ruled that meat from cloned cattle, pigs and goats is
as safe to eat as meat from conventionally bred livestock. GM animals, however, fall
under different legal provisions and as such must receive formal approval before they
can be sold for human consumption.
If, as expected, the FDA eventually approves the sale of the GM salmon, it will mark
an important precedent in the technological changes to the human food chain that
some scientists believe are essential if we are to feed the extra three billion people
expected to be living on the planet by the middle of the century. Its approval will
lead to calls for similar licences in Britain and the rest of Europe.
AquaBounty Technologies argues that biologically the fish are no different to wild
salmon, yet can be grown on fish farms more efficiently than conventional farmed
salmon, making them less harmful to the environment. Because GM salmon are
designed to be reared in tanks on land, they are closer to the markets, thus lowering
transport costs and the corresponding carbon footprint.
Scientists have warned that the marine environment, which has already suffered
from decades of intensive overfishing, is close to collapse. Yet the demand for fish
has increased at a time when stocks have dwindled. Humans face a stark choice
between giving up eating many kinds of wild-caught fish, or turning to alternatives
such as captive-bred animals. GM technology offers one potential solution to the
problem of feeding a growing human population, but it is one solution among many.
What is clear is that an overwhelming proportion of consumers have yet to be
convinced of the benefits of GM animals for food.
GM Foods: The facts
Genetically modified (GM) animals are created using a technology which alters their
DNA, thus changing their genetic make-up permanently. Often these "transgenic"
animals have DNA inserted into their genome from another, unrelated species.
Agricultural researchers have experimented extensively with GM technology to
improve the performance of domestic animals. Growth-hormone genes were seen as
a way of boosting muscle growth, but many early experiments were stopped after
The most notable failure in this research was the "Beltsville pig" produced by the US
Department of Agriculture in the early 1980s. The pig had a human growth-hormone
gene inserted into its DNA which was supposed to make it grow faster and leaner.
However, this caused disturbing growth deformities that crippled the animals.
Other attempts at creating GM animals have focused on the possibility of producing
valuable human proteins in their milk. This "biopharming" was seen as a way of
making new drugs that could not be easily made by other means.
Similar research has centred on creating GM animals with organs that could be
transplanted into humans without fear of tissue rejection.
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