Cloned animals 'safe to eat'

By Richard Black BBC Science Correspondent

An influential committee of scientists in the USA has declared that eating food made from cloned animals appears to be safe.

However, it says that products made from genetically-modified animals could pose a risk to human health.

It also believes that animals created both by cloning and genetic modification raise significant concerns over environmental risks and animal welfare.

The committee was set up by the National Academy of Sciences in response to a request from the US government.

The government's regulatory body, the Food and Drug Administration, is currently debating whether it should allow the sale of GM meat and milk.

Its decision is anticipated by the end of the year, and the committee's report will be influential in deciding whether it approves these products for market or rejects them.

Data deficit

The committee admits that data is scarce, particularly on animals cloned from adult tissue, like Dolly the sheep - the technique known as somatic nuclear transfer.

"Limited sample size, health and production data, and rapidly changing cloning protocols make it difficult to draw conclusions regarding the safety of milk, meat or other products from somatic cell cloned individuals," it says.

Cloned meat and milk in US shops next year?

Some evidence comes from animals cloned by different, older techniques. Over two thousand Holstein cattle have been cloned since the 1980s in the USA, using methods called embryo splitting and blastomere nuclear transfer, BNT.

These techniques have not been adopted widely, mainly because they do not improve yields.

"Food products from BNT clones have been consumed by humans, with no apparent ill effects," the report says. But it urges the Food and Drug Administration to run tests on food made from cloned animals.

On genetically-engineered animals, the report is more equivocal.

It says that with any genetically-modified organism, there is a large degree of uncertainty about how, when and where inserted genes will turn themselves on.

New genes inserted into the DNA of GM animals will make proteins which are not normally present in the human diet, the report says. These could produce allergic reactions, or even be poisonous.

The committee concludes that some GM animal products may pose what it calls a "moderate degree of concern" .

The report was welcomed by the Biotechnology Industry Organisation, BIO, a lobby group based in Washington DC.

"It's very positive. They found no evidence of any danger from drinking milk or eating meat made from cloned or genetically-engineered animals," said spokeswoman Lisa Dry.

"That's the same as we've found with genetically-engineered crops."

According to BIO, there are currently about six companies in the world producing farm animals by cloning or genetic engineering.

Flying fish

The main issue with GM animals, the committee says, is the potential spread of inserted genes into the wild.

End for wild salmon?

Fish, it says, present a particular problem. GM salmon which start life in farms may well escape into rivers and seas; and if they are bigger or fitter than normal salmon, their genes will spread through wild populations.

Modified species might also be able to establish themselves in new areas of land or water. "A transgene that increases fitness or adaptations increases the risk of establishment and results in the highest level of concern," the report concludes.

The other concern the scientists raise is animal welfare.

The report notes that some cloned animals, including cattle, have health problems around the time of birth, with some calves growing so big that they cannot be born naturally.

This aspect of the report drew approval from Dr Sue Mayer of GeneWatch, an independent UK-based research group.

"The committee has said that substantial differences can occur in genetically-engineered and cloned species," she said. "That means they need to be treated differently."

Coming revolution

So far, the genetic revolution has largely passed animal farming by; but the committee expects this to change.

"Many of these recent advances have not yet left the experimental stage," they say, "But it is clear that that several, including transgenic finfish, which are soon likely to be commercialised, are likely to assume importance."

The biotechnology industry sees GM animals as providing several benefits to consumers.

"You could make animals with less fatty meat, or more nutritious milk," according to Lisa Dry. "Or they could be more resistant to diseases, which could make them safer for humans to eat."

But Sue Mayer disagrees. "We're deeply concerned that anyone is thinking of producing farm animals by such techniques," she said. "There are much better ways of solving the world's agricultural problems."