The Observer, Saturday 29 October 2011
Stem cells with growing nuclei. These cells can become any cell in the body when they divide. Photograph: David Mack/Science Photo Library
The dream of regenerating human organs is as old as Prometheus. Chained to his rock, the Titan survived attacks by an eagle that feasted on his liver by growing it anew under cover of darkness. When Mary Shelley wrote Frankenstein, her shocker on the creation of life, she gave it the alternative title The Modern Prometheus.