Sheep: Dolly clones now growing to old age
Category : Sheep
Dolly the sheep made headlines when, 20 years ago, she was the first large mammal that was successfully cloned. She aged prematurely, though, and had to be euthanized at age six. Now, four of her cloned offspring at the University of Nottingham, are showing that clones can live to an older age – they’re already nine years old – and proving that the somatic-cell nuclear transfer cloning process is becoming more efficient.