GM hens lay cancer drug protein

In collaboration with the Press Association

UK scientists have developed genetically modified chickens that can lay eggs containing hard-to-generate proteins used to treat cancer.

The flock of hens, developed at Edinburgh's Roslin Institute, could cut the cost of drug production. Roslin researchers made history in 1997 when they created Dolly, the first cloned animal.

In addition to anti-cancer proteins, the researchers were able to create the basic biological ingredients for potential arthritis and multiple sclerosis treatments in the egg whites of the chickens.

The complex active ingredients in these drugs are proteins known as monoclonal antibodies. In order to make the quantities required for treatment, antibodies are normally grown in vats of cells.

By splicing human genes for antibodies with the chicken gene that makes a component of egg white, lead-researcher Dr Helen Sang was able to demonstrate a cheaper alternative.

"Anything that allows us to expedite the number of novel therapeutics that we can offer cancer patients and also potentially reduces the cost of their manufacture must be welcomed," said Professor Herbie Newell of Cancer Research UK.

The hens are a common breed and each produces up to 300 eggs a year. So far, the researchers have bred five generations of hens that laid eggs containing the engineered proteins.