Science News

Researchers Cloning Cows To Prevent Bse

The recent discovery in the US of a cow suffering from BSE or mad cow disease has prompted a group of scientists at the Virginia-Maryland Regional College of Veterinary Medicine to attempt to clone cows that are genetically engineered to prevent them from developing the disease. Drs. Will Eyestone and Bill Huckle are attempting to remove the gene that codes for the so-called prion protein that causes BSE. All animals, including humans, make prion proteins which are normally roll up like a ball of wool. But in BSE the protein becomes abnormally folded into fibrous sheets which can kill nerve cells and leave the brain full of holes like a swiss cheese. Worse still, the abnormally folded prion protein can then convert other healthy prions to the abnormal form. The disease spreads when material containing the abnormal prion protein is fed to healthy animals, gets into the brain and triggers off the disease again. But scientists have shown that animals engineered to lack the prion protein appear to be healthy but, crucially, cannot develop BSE-like diseases. The researchers are hoping that cows genetically engineered and cloned to lack the essential prion protein will not be at risk from developing BSE. But with 100 million cattle in America they have their work cut out for them !

18th Jan 2004