Wilmut was the leader of the research group that in 1996 first cloned a mammal, a lamb named Dolly. Dolly died of a respiratory disease in 2003. However, in 2008 Wilmut announced that he would abandon the technique of somatic cell nuclear transfer by which Dolly was created in favour of an alternative technique developed by Shinya Yamanaka. This method has been used in mice to derive pluripotent stem cells from differentiated adult skin cells, thus circumventing the need to generate embryonic stem cells. Wilmut believes that this method holds greater potential for the treatment of degenerative conditions such as Parkinson's disease and to treat stroke and heart attack patients.