STOCKHOLM — Two scientists from different generations won the Nobel Prize in medicine Monday for the groundbreaking discovery that cells in the body can be reprogrammed to become completely different kinds, potentially opening the door to growing customized tissues for treatments.
The work of British researcher John Gurdon and Japanese scientist Shinya Yamanaka — who was born the year Mr. Gurdon made his discovery — has raised hopes of developing transplant tissue to treat diseases like Parkinson's and diabetes.
And it has spurred a new generation of laboratory studies into other diseases, including schizophrenia, that may lead to new treatments.
Basically, their work paved the way to making the equivalent of embryonic stem cells without the ethical questions the embryonic cells pose.
"Their findings have revolutionized our understanding of how cells and organisms develop," the Nobel committee at Stockholm's Karolinska Institute said in announcing the $1.2 million award.
It is the first of this year's Nobel Prizes, with five more awards to be announced by next Monday.
Mr. Gurdon, 79, showed in 1962 that the DNA from specialized cells of frogs, like skin or intestinal cells, could be used to generate new tadpoles. That showed the DNA still had its ability to drive the formation of all cells of the body.
At the time, the discovery had "no obvious therapeutic benefit at all," Mr. Gurdon told reporters in London. "It was almost 50 years before the value — the potential value — of that basic scientific research comes to light."
In 1997, the cloning of Dolly the sheep by other scientists showed that the same process Mr. Gurdon discovered in frogs would work in mammals.
More than 40 years after Mr. Gurdon's discovery, in 2006, Mr. Yamanaka, 50, showed that a surprisingly simple recipe could turn mature cells back into primitive cells, which in turn could be prodded into different kinds of mature cells.
Basically, the primitive cells were the equivalent of embryonic stem cells, which had been embroiled in controversy because to get human embryonic cells, human embryos had to be destroyed. Mr. Yamanaka's method provided a way to get such primitive cells without destroying embryos.
"The discoveries of Gurdon and Yamanaka have shown that specialized cells can turn back the developmental clock under certain circumstances," the Nobel committee said. "These discoveries have also provided new tools for scientists around the world and led to remarkable progress in many areas of medicine."
Just last week, Japanese scientists reported using Mr. Yamanaka's approach to turn skin cells from mice into eggs that produced baby mice.
Mr. Gurdon has served as a professor of cell biology at Cambridge University's Magdalene College and is currently at the Gurdon Institute in Cambridge, which he founded.
Mr. Yamanaka worked at the Gladstone Institute in San Francisco and Nara Institute of Science and Technology in Japan. He is currently at Kyoto University and also affiliated with the Gladstone Institute.
Mr. Yamanaka is the first Japanese scientist to win the Nobel medicine award since 1987.
Mr. Gurdon said he first thought someone was "pulling my leg" when he got the call from the Nobel committee. He said he planned to celebrate with a drink, but expected to be back in the lab Tuesday morning and that he has no plans to retire.
Mr. Yamanaka told Japanese broadcaster NHK that he was at home doing chores on Monday when he got the call from Stockholm. "Even though we have received this prize, we have not really accomplished what we need to. I feel a deep sense of duty and responsibility," he said.