The 2012 Nobel Prize in Medicine was awarded Monday in Stockholm to a Japanese and a British through their work on the reversibility of stem cells, which can create all types of body tissues. Biologist John Gurdon, born in 1933, and the doctor and researcher Shinya Yamanaka, 50, won the prize for their research on nuclear reprogramming, a technique that can transform adult cells into stem cells not specialized expertise. They were named in the press as the big favorites. The Nobel committee said they have been rewarded for having discovered that "adult cells can be reprogrammed to become pluripotent (ability to differentiate into several cell types ed)." "Their discoveries have revolutionized our understanding of how cells and organisms grow," said the Nobel committee. In 1962, Mr. Gurdon was a breakthrough in discovering, not even 30 years while his co-winner Dr. Yamanaka was not born, that the specialization of cells was reversible. He was working on tadpoles and frog. "The books were then rewritten and new fields of research established. Reprogramming in human cells, scientists have created new opportunities to study disease and develop methods for diagnosis and therapy," summed up the jury . "Shinya Yamanaka discovered more than 40 years later, in 2006, how adult stem cells intact mice could be reprogrammed to become immature stem cells," said the Nobel committee. His work has set adult differentiated cells that revert versatile, opening infinite potential in cell therapy. They advantageously replace embryonic stem cells, and eliminate the risk of rejection. But there is still some way to go before ensuring their complete safety: one of the risks is that of uncontrolled cell proliferation. Are also tools for screening pharmacological or toxicological or models of human diseases, since these findings have to reprogram somatic cells of patients with diverse diseases. Mr. Gurdon works at the University of Cambridge since 1972. M. Yamanaka, who was first orthopedic surgeon, then turned to research, and now works at the University of Kyoto, while also being affiliated Gladstone Institute, a research institute of San Francisco ( USA). They follow the American Bruce Beutler, Jules Hoffmann at the French and Canadian Ralph Steinman honored for their work in 2011 on the immune system. Medicine is awarded the first Nobel Prize in 2012. It will be followed by physics Tuesday, chemistry Wednesday, literature on Thursday and Friday of peace. The economy will finish the season Monday. The Nobel Foundation has decreased this year the award by 20% to 8 million kroner (930,000 euros) against 10 million since 2001. The two winners will share the price will be at a ceremony in Stockholm on Dec. 10, the anniversary of the death of the founder of the prize, the Swedish industrialist Alfred Nobel.