Monday, 20 October 2008

Super-cows to give mothers’ milk

Scientists use genetic engineering to produce human protein

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Guanyu said...

Super-cows to give mothers’ milk

Scientists use genetic engineering to produce human protein

Stephen Chen
20 October 2008

Mainland scientists have raised genetically modified cows that can produce an important protein found only in mother’s milk, Xinhua has reported.

The unique protein is called human lactoferrin, an antioxidant that binds and transports iron in the human body. It efficiently kills bacteria and can play an active role in the defence systems of infants and adults.

For decades, human lactoferrin has only been found in breast-fed infants and efforts to duplicate it in animal milk have failed.

But scientists at the State Key Laboratory of Agro-Biotechnology recently modified the genetic sequence in a group of cows, enabling them to produce the protein, according to Xinhua.

The scientists were not the first to create such a “magic” cow, but they may be the first to make the technology commercially viable, the report said.

Li Ning, director of the laboratory, said the team spent more than seven years screening for a cow species that could meet the demand for industrialised production.

Finnish scientists demonstrated in 1994 that genetically modified mice could produce milk with human lactoferrin, and German scientists created the first cow to do so in 2002.

Since then, many countries have tried to increase the concentration of the protein to make it profitable, but had failed to do so.

Professor Li told Xinhua yesterday the yield of recombinant human lactoferrin from Chinese cows was the highest in the world. He did not reveal the concentration, but said the technology was ready for large-scale production.

The technology will need at least two years to pass examination by the national food safety authority.

The research has been funded by the state and investment from private companies.

The central government has spent large sums on transgenic programmes and recently allocated more than 30 billion yuan (HK$34 billion) to the field. Though mainland scientists admit they still lag behind scientists in developed countries in terms of basic research, they are more or less on par with the world’s best in terms of applied research.

Premier Wen Jiabao, in an interview with Science magazine last month, strongly supported the genetic modification research and said it would increase farmers’ income.

Mainland dairy producers will likely welcome the technology, as it not only improves the quality of the milk, but also benefits the cows because the protein can eliminate common bacteria that cause mastitis, or inflammation of the udders.

Most baby milk powder on the market today uses non-human lactoferrin. Though it is highly concentrated, it cannot be properly absorbed by the digestive system.

But some consumers, especially mothers whose fear of the tainted milk crisis lingers, have doubts about the technology.

Li Li, mother of a newborn, said: “A simple chemical like melamine is easy to detect and its damage is instant and obvious.

“But fiddling with the genetic sequence? Who can guarantee it won’t become just another scandal in 10 years’ time?”