Scientists develop genetically modified cows that produce ‘human’ breast milk
By David Derbyshire
Babies could be fed on ‘human’ milk produced by cows in the wake of the latest developments in genetic modification.
Scientists have bred 300 cattle that have been given human genes to make their milk contain the same nutrients and fat content as breast milk.
They believe the product could offer mothers an alternative to conventional infant formula.
But the move was condemned last night by campaigners who questioned its safety.
Human milk differs from cows’ milk in several important ways. It contains high quantities of nutrients beneficial to a baby’s growth and immune system.
Cows’ milk is much harder for a baby to digest, has less fat and fewer carbohydrates and contains no antibodies that protect against disease.
Prof Ning Li, who led the research at the China Agricultural University, said the milk they produce would be as safe as ordinary cows’ milk.
‘The milk tastes stronger than normal milk,’ he said. ‘Within ten years, people will be able to pick up these human-milk-like products at the supermarket.’
But Patti Rundall, of Baby Milk Action, said: ‘We need to have rules in place to safeguard human health.
‘There could be incredible risks with these products that we don’t know about. Cows’ milk is never going to be like breast milk. It’s never going to be a living product like breast milk.
Writing in the respected journal Public Library of Science One, Prof Li’s team said they used cloning technology to introduce human genes into the DNA of Holstein dairy cows.
One variety of the GM cows produced milk containing lysozyme – an antimicrobial protein found in breast milk that protects babies from infection. They also created cows that produced human lactoferrin, a protein which boosts the immune system.
A third human milk protein called alpha-lactalbumin was also expressed in the milk. Prof Li claims his team has boosted the milk’s fat content by a fifth and changed the levels of solids to make it close to the composition of human milk.
But campaigners said the creation of GM cattle was bad for animal welfare. In two experiments by the Chinese in which 42 GM calves were born, just 26 survived. Ten died soon after birth and six died within six months.
A spokesman for the Royal Society for the Protection of Animals said: ‘Offspring of cloned animals often suffer health and welfare problems, so this would be a grave concern. Why do we need this milk – what is it giving us that we haven’t already got?’
Helen Wallace, of watchdog GeneWatch UK, said: ‘There is a question about whether milk from these cows is going to be safe for humans, and it is really hard to tell that unless you do large clinical trials.’
China’s rules on GM food are more relaxed than those in Europe. The GM milk would not be allowed on sale in Britain unless it was approved by the European Union and passed stringent safety tests.