This is the VOA Special English Health Report.

This year's Nobel Prize in medicine will go to three researchers who found a way to learn about the duties of individual genes. They discovered how to inactivate, or knock out, single genes in laboratory animals. The result is known as "knockout mice." 

The Karolinska Institute named the winners last week. Two Americans, Mario

Mario Capecchi holds a laboratory mouse

Capecchi and Oliver Smithies, will share the one and one-half million dollar prize with Martin Evans of Britain. They will receive what is officially called the Nobel Prize in Physiology or Medicine at a ceremony in Stockholm, Sweden, on December tenth.

In the nineteen eighties, Mario Capecchi and Oliver Smithies both studied cells in mice to find how to target individual genes for changes. But the kinds of cells they independently studied could not be used to create gene-targeted animals.

Martin Evans had the solution. He developed embryonic stem cells that could produce mice that carried new genetic material.

The research greatly expanded knowledge about embryonic development as well as aging and disease. It led to a new technology -- gene targeting. And this has already produced five hundred mouse models of human conditions.

Knockout mice are used for general research and for the development of new treatments. International efforts aim to make them available in the near future for all genes.

Mario Capecchi is a researcher at the University of Utah. He was born in Italy in nineteen thirty-seven. He was homeless and on his own for years as a young boy.

His mother had been sent to a Nazi German death camp. But she survived, and after she was freed she found him in a hospital. He was nine years old and being treated for severe malnutrition.

They came to the United States where he entered school for the first time. Later, he became an American citizen.

Oliver Smithies

Oliver Smithies was born in Britain in nineteen twenty-five and also became an American citizen. He is a professor at the University of North Carolina. And, at age fifty, he learned to fly. He flies a motor glider and small airplanes.

Martin Evans was born in nineteen forty-one, also in Britain. He is director of the School of Biosciences at Cardiff University in Wales. He called winning the Nobel Prize "a boyhood dream come true."

And that's the VOA Special English Health report, written by Caty Weaver. Transcripts and MP3 files of our reports are at voaspecialenglish.com. I'm Barbara Klein.