Scientists create anti-cancer chicken eggs

The researchers behind the first cloned sheep said they have developed genetically modified chickens that can lay eggs containing proteins needed to make cancer-fighting drugs.

The Roslin Institute, near Edinburgh in Scotland, said it has produced five generations of birds capable of producing useful levels of life-saving proteins in egg whites.

The director of the institute, which clonedDolly the sheep,told the BBC that the work could lead to cheaper and more readily available drugs.

The findings will be published this week in the Proceedings of the National Academy of Sciences.

"One of the characteristics of lots of medical treatments these days is that they're very expensive," said Prof. Harry Griffin.

"The idea of producing the proteins involved in treatments in flocks of laying hens means they can produce in bulk, they can produce cheaply, and indeed the raw material for this production system is quite literally chicken feed."

The institute told the BBC it has bred about 500 modified birds. Some have been engineered to lay eggs containing miR24, an antibody with potential for treating melanoma,the deadliestform of skin cancer.

Others lay eggs containing human interferon b1a, which can be used to stop the replication of viruses. The proteins are found in egg whites.

The scientists at Roslin cautioned it would be another five years before patient trials are approved and another10 yearsbefore medicine is developed.