Researchers have created a calf whose milk could be drunk by those who are lactose intolerant. 
Researchers have created a calf whose milk could be drunk by those who are lactose intolerant. Photo: Quentin Jones
SCIENTISTS have genetically modified calves so that the milk they produce as cows will be healthier for humans.

In separate breakthroughs, researchers have created a calf that, when it becomes a cow, will produce milk that can be drunk by people who are lactose intolerant. Milk from a second animal, when adult, will contain high levels of the kind of healthy fat found in fish.

The GM calves are part of a growing effort by scientists to make healthier food and drink products from livestock by genetically altering the animals.
The work is likely to inflame the debate about the ethics of GM foods. Critics of the technology have reacted angrily to the research and questioned the safety of milk from GM animals.

Geneticists have introduced a gene into cow embryos that causes lactose, the principal sugar in dairy products, to break down into other types of sugar that are more easily digestible by humans.

Three calves were born after 14 GM embryos were implanted into surrogate cows. The one surviving calf, Lucks, is expected to start producing low-lactose milk after she gives birth at about two years of age.

Dr Zhou Huanmin, the director of the state laboratory for biomanufacturing at the Inner Mongolia University where the calf was created, said the team hoped to have lactose-free milk in the shops in about five years.

''Most people suffer the lactose intolerance in varying degree,'' he said. ''We are attempting to breed a dairy cow that will produce low-lactose milk for supplying the market. We hope to commercialise it in the future.''

In Britain about 5 per cent of people are lactose intolerant, but in some parts of Africa and Asia up to 90 per cent of the population do not have the ability to digest milk properly.

In a separate study, published in Transgenic Research, another group of scientists at the Inner Mongolia University has created a GM calf they hope will produce milk with high levels of omega 3 fatty acids.

The research has concerned animal rights groups and critics of GM technology. Dr Helen Wallace, the director of Genewatch, which monitors genetic technology, said: ''As with all GM technology, there is a potential for unintended consequences as it is interfering with the natural biological production pathways.''