Nobel Prize for medicine awarded to Gurdon, Yamanaka for stem cell discoveries

British scientist John Gurdon and Japanese researcher Shinya Yamanaka shared the 2012 Nobel Prize in physiology or medicine Monday for experiments separated by almost 50 years that provide deep insight into how animals develop and offer hope for a new era of personalized medicine.

Their findings have revolutionized our understanding of how cells and organisms develop, the Nobel committee said in the prize announcement.

In 1962, Gurdon wowed the world of biology by cloning a frog via a clever technique. He transplanted the genetic material from an intestinal cell of one frog into the fertilized egg cell from another. The egg developed into a tadpole, proving that all of the genetic instructions needed to turn an embryo into an adult exist even in so-called adult cells of the body the specialized cells that make up skin, muscle, nerves and other tissues.

In 2006 and 2007, Yamanaka extended that insight by turning back time on individual cells from both mice and humans. By sprinkling four genes on ordinary skin cells, Yamanaka discovered a virtual fountain of youth for cells: Any type of cell, he found, could be reverted to a young, embryonic state. These induced embryonic cells behave much like the ethically contentious stem cells gleaned from human embryos. They can be grown into many other types of tissues but without having to destroy any embryos.

The breakthrough offered hope that someday, skin cells could be harvested from a patient, sent back in time to an embryonic state, and then grown into replacement tissues such as heart muscle or nerve cells.

Yamanakas breakthrough has spawned a huge research global effort to turn these induced pluripotent stem cells, as theyre called, into therapies tailored to individual patients for a wide range of ailments, including heart disease, some forms of blindness, Parkinsons disease and many other disorders.

The first human trials of such therapies could begin next year, Yamanaka told the journal Nature earlier this year. He said eye diseases present an attractive target for the first tests.

On Monday, Yamanaka credited his co-laureate for making his advances possible. This field has a long history starting with John Gurdon, he said in a brief telephone interview posted on the Nobel Prize Web site. Yamanaka noted he was born in 1962 the year Gurdon published his pivotal frog experiments.

A surgeon by training, Yamanaka, who splits his time between Japans Kyoto University and the University of California, San Francisco, said treating patients has always been his aim. My goal all my life is to bring this stem cell technology to the bedside, to patients.

But the therapeutic potential of induced stem cells remains in question. Some experiments show the cells may form tumors, prompting skepticism that they will ever be safe enough to treat heart disease, Parkinsons disease and many other conditions where specific cells of the body break down.