FACTBOX - Nobel medicine prize - Who are the winners?

(Reuters) - Mario Capecchi, Martin Evans and Oliver Smithies won the 2007 Nobel prize for medicine or physiology for their work on stem cells, Sweden's Karolinska Institute said on Monday.

Here are some details about the winners:

* MARIO CAPPECCHI:

-- Mario Capecchi was born Italy in 1937 and is a U.S. citizen. He received his B.S. degree in chemistry and physics from Antioch College in 1961 and his Ph.D. in biophysics from Harvard University in 1967.

-- Capecchi is best-known for his pioneering work on the development of gene targeting in mouse embryo-derived stem (ES) cells. This technology allows scientists to create mice with mutations in any desired gene.

-- The power of this technology is that the investigator chooses both which gene to mutate and how to mutate it. The investigator has virtually complete freedom on how to manipulate the DNA sequences in the genome of living mice.

* MARTIN EVANS:

-- Martin Evans was born in Britain in 1941. After graduating from the University of Cambridge in 1963, he gained his PhD at University College, London.

-- In 1978, he returned to the University of Cambridge and it was here he discovered embryonic stem cells in mice with his collaborator Dr Matthew Kaufman in 1981.