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A team of British scientists developed through genetic modified chickens that can lay eggs with proteins needed to make anticancer drugs. The breakthrough was announced by the same research center that created a little over ten years, the first mammal cloned from an adult cell, Dolly the sheep. The Roslin Institute, near Edinburgh, Scotland, said it has produced five generations of these birds, a total of about 500. "One of the characteristics of many current medical treatments is that they are very expensive," he told the BBC the institute's director, Harry Griffin. "The use of laying hens to produce proteins for treatment means that they can produce in large quantities cheaply and, in fact, the only raw material needed

in this production system is literally food for chickens," he added. The only raw material needed in this production system is literally food for chickens Harry Griffin, director of the Roslin Institute The project is the result of more than 15 years of work of the research team leader, Dr. Helen Sang. However, the institute warned that it could take another five years before any possibility of human clinical trials and ten until they can produce drugs. Antiviral approach For years, there are therapeutic proteins, like insulin, in bacteria, but there are complex proteins that can be manufactured only in the more sophisticated cells of larger organisms. The transgenic chickens could boost the production of cheaper drugs. Scientists from various countries have succeeded in making a range of these molecules in the milk of sheep, goats, cows and rabbits, all modified by genetic pathway. The work carried out at the Roslin Institute also shows that the hens can be used as "biofactories." Some of the birds have been modified to lay eggs that contain miR24 protein, a type of antibody that could be used to treat malignant melanoma. Others produce human interferon b-la, which can be used to prevent virus replication in cells. The proteins are secreted into the whites of the eggs and extract and purify process is very simple. Productivity Dr Sang said the team is very encouraged by the level of productivity of the birds, but they must make improvements. "We're probably getting a high enough productivity to very active protein like interferon, but not enough to make antibodies because people need large doses of these over long periods," he told the BBC. One of our next challenges is to seek to clear performance Dr. Helen Sang, head of the team "One of our next challenges will be trying to increase the yield in the clear." The scientist noted that the use of birds has certain advantages over other animals because of these life cycles are shorter. "Once you have created transgenic birds, it is very easy. After successfully introduced a gene, can get hundreds of birds from one cockerel." "As you can play with hundreds of chickens, one can get an egg a day, and produce hundreds of chicks in no time," he said. Reproductive Biology The team also hopes that the birds changed offer new information on different aspects of reproductive biology, including fundamental processes that control the early development of vertebrates. The Roslin Institute's research is part of the Avian Transgenic Project, a joint venture with biotechnology firms Viragen and Oxford BioMedica.