This year’s Nobel Prize in Physiology or Medicine has jointly gone to John Gurdon of Cambridge University in Britain and Shinya Yamanaka of Kyoto University in Japan.

Gurdon is called the pioneer of cloning and bio engineering research after he discovered that the specialization of cells is reversible in 1962 when he was a graduate school student.

In an epoch-making experiment, Gurdon showed that a frog egg modified with the DNA from the mature intestinal cell of a frog could be developed into a normal tadpole.

The Nobel Assembly at Karolinska Institutet decided to also award the Nobel Physiology or Medicine Prize to Yamanaka in recognition of his achievement of a scientific breakthrough in embryonal stem cell research. He and his coworkers introduced four genes together to the skin cells of mice to produce pluripotent stem cells that can develop into any type of mature cells.