High Quality Content by WIKIPEDIA articles! Mario Renato Capecchi (Verona, Italy, 6 October 1937) is an Italian-born American molecular geneticist and a co-winner of the 2007 Nobel Prize in Physiology or Medicine for discovering a method to create mice in which a specific gene is turned off (knocked out). He infected embryonic stem cells with a viral vector that was designed to incorporate itself into the target gene by homologous recombination. Homologous recombination is a process that cells normally use to repair their DNA, which is exploited by viruses to infect cells. He shared the prize with Martin Evans and Oliver Smithies. He is currently Distinguished Professor of Human Genetics and Biology at the University of Utah School of Medicine, which he joined in 1973.