The exciting possibility that mature body cells, such as skin cells, might be transformed and used to repair damaged hearts or brains was long seen as science fiction. Once a cell had reached its specialised mature state, biologists thought, it could not adopt another identity. John Gurdon, who has died aged 92, was the first to show that it could. In 2012 he shared the Nobel prize for medicine with the Japanese researcher Shinya Yamanaka for this discovery.
In 1958, while still a graduate student at Oxford University, Gurdon reported that he had removed the nuclei, which contain the cell’s DNA, from frog eggs and successfully replaced them with nuclei taken from cells lining the guts of tadpoles.
