Professor Sir Martin Evans
One of the greatest challenges in science is the battle against currently incurable diseases; everything from cancer, to Parkinson's and cystic fibrosis. Stem cell technology is the great hope of a generation of researchers and all of them owe a debt to Professor Sir Martin Evans. His ground breaking work on embryonic stem cells has been rewarded with this year's Nobel Prize in Medicine. Stephen Sackur asks if stem cells are really going to change our lives.