KEY POINTS:
Scientists have coaxed human skin cells into mimicking the disease-fighting potential of embryonic stem cells.
The startling breakthrough, reported almost simultaneously by two separate laboratories, could help sidestep the ethical controversy over using embryonic stem cells.
Embryonic stem cells can develop into any kind of tissue, and are widely considered to hold great hope of treatments and cures for many diseases - but the embryos are destroyed in the process of extracting the cells.
Now scientists in Japan and the US have reported virtually identical discoveries in creating cells that act like stem cells, but by using skin cells instead of embryos.
One of the teams did it using skin cells from the face of an unidentified 36-year-old woman, the other, foreskin cells from a newborn. The cells came from a tissue supplier.
Each team used viruses to ferry four genes into the skin cells. These particular genes were known to turn other genes on and off, but just how they produced cells that mimic embryonic stem cells is a mystery.
Scientists familiar with the new technique, called "direct reprogramming" and reported in the journals Cell and Science on Tuesday, said scientific questions remained and it was still important to pursue embryonic stem cell research, but the new work was a major development.
"It's a bit like learning how to turn lead into gold," said Dr Robert Lanza, chief science officer of Advanced Cell Technology, which has been trying to extract stem cells from cloned human embryos.
Auckland University neuropharmacologist Dr Bronwen Connor expected the new technique, which she would consider using in future, would accelerate stem cell research.
The Government is developing guidelines on embryonic stem cell research. Creating embryonic stem cell lines is not permitted in New Zealand, but they can be imported.
The new technique is not without problems. It requires disruption of the DNA of the skin cells, which creates the potential for developing cancer, a weakness that would prevent its therapeutic use. However, experts believe this problem can be overcome.
Last year, Dr Shinya Yamanaka, of Kyoto University in Japan, reported that direct reprogramming in mice had produced cells resembling embryonic stem cells, although with significant differences.
In June, his group and two others announced they had created mouse cells that were virtually indistinguishable from stem cells.
Scottish scientist Ian Wilmut, who cloned Dolly the sheep, said he was giving up the cloning of embryos to produce stem cells, and intended to take up direct reprogramming instead.
MAGIC BULLET
* Stem cells from human embryos are able to develop into any kind of tissue.
* It is hoped that in future they could be used to treat spinal cord injuries, diabetes, stroke, epilepsy, Parkinson's disease and many other ailments.
* But extracting the cells destroys the embryo, making the concept ethically controversial.
* Now scientists have produced very similar cells without embryos.
* In the new method, human skin cells have four genes inserted into them through a virus.
* This genetically reprogrammes the cells to return to the more primitive state of stem cells.
* Scientists have shown that these cells could grow into different tissue, including beating heart cells and nerve cells.