stem cells without destroying life-- part 1

Excerpts from Guatam Naik in the WSJ on the recent advance in adult stem-cells...

Scientists have created embryonic stem cells without using eggs or destroying embryos, an advance that may sidestep the knottiest ethical dilemmas that have slowed stem-cell research.

In experiments on mice, four independent teams pulled off a feat that is the biological equivalent of turning back time: They returned mature cells -- such as those from skin -- to a primordial, embryonic state. Further experiments showed that those reprogrammed cells had the same properties as true embryonic stem cells, such as the ability to turn into muscle, heart, nerve and other tissue types -- no matter what kind of mature cell they had started as.

"We've shown that we can reset the clock," says Rudolf Jaenisch, a scientist at the Whitehead Institute for Biomedical Research in Cambridge, Mass., and lead author of one of the studies, which is published in the journal Nature. However, he cautions, "we're very far away from this being turned into routine medical treatment." (See more on Nature's site.)

Crucially, three of the experiments didn't use eggs or require the destruction of embryos, which some people believe is immoral because it kills nascent human life....

Now, how's the following for irony?

It all started with the birth of Dolly, a cloned sheep, a decade ago. Scientists in Britain created Dolly by taking genetic material from the mature skin cell of her "mother" and substituting it for the genetic material inside the nucleus of another sheep's egg. To their surprise, the egg mysteriously "reprogrammed" the skin cell and returned it into an embryonic state -- from which Dolly was then born. The experiment involved cloning, an obviously controversial move if applied in humans. But for a small group of scientists it sparked an intriguing question: Could mature cells be reprogrammed in other ways that don't require cloning?

Shinya Yamanaka of Kyoto University made the breakthrough....Each of the research teams focused on four specific genes that Dr. Yamanaka had identified last year. Using viruses as a transport vehicle, the scientists inserted the four genes into mature mouse cells and were able to return them to their youthful, embryonic stage. They were then able to implant those cells into embryos that produced healthy mice. In addition, the offspring of those mice also carried the genetic information from the reprogrammed cells, passing a sort of double-gold-standard test.

Achieving the same result in humans is likely to be a far tougher challenge....