Dolly cloned sheep

Recent, but undated, file picture of Dolly the sheep, the world's first cloned adult animal. Dolly, who is now seven-months-old, was developed by a team at Edinburgh's Roslin Institute. * 14/08/00 The scientists who cloned Dolly the Sheep are to stop experiments involving genetically modifying pigs for human organ transplants because of concerns that deadly new diseases could be passed on to people. 04/01/02: Dolly, the world's first cloned sheep, who has arthritis in her left hind leg at the hip and the knee. Professor Ian Wilmut, of the Edinburgh-based Roslin Institute who led the team which cloned the animal, said there was no way of knowing if the five-year-old's condition was a result of the cloning process. (Photo by PA Images via Getty Images)