SAFE and ethical stem cell treatments for a host of diseases are closer to becoming a reality following a breakthrough by Scottish scientists.
Researchers from Edinburgh University, along with scientists in Canada, have found a way to reprogramme skin cells so they can assume the properties of stem cells obtained from embryos, with the potential to become virtually any kind of body tissue.
Previously, it was only possible to create these "induced pluripotent stem" (iPS) cells using viruses to insert the four genes that carry out the reprogramming.
But the viruses modified the cells' DNA in such a way that the procedure greatly increased the risk of cancer, making the technique too risky for human patients.
The breakthrough raises the prospect for the first time of developing wide-ranging stem cell treatments without having to destroy human embryos.
The research was led by Dr Keisuke Kaji, from the Edinburgh-based Medical Research Council's Centre for Regenerative Medicine, and Dr Andras Nagy, from Toronto University.
The technique, revealed last night in the online version of the journal Nature, was developed both in mouse and human skin cells.
Tests on the reprogrammed cell lines showed that they behaved exactly like embryonic stem cells.
Professor Sir Ian Wilmut, director of the Medical Research Council's Centre for Regenerative Medicine, said it would be some time before the cells could be given to patients. "Crucially, we need to have a method to generate the desired cell types from these stem cells.
"But I believe the team has made great progress and, combining this work with that of other scientists working on stem cell differentiation, there is hope that the promise of regenerative medicine could soon be met." Dr Kaji added: "I was very excited when I found stem cell-like cells in my culture dishes. Nobody, including me, thought it was really possible. This new method will advance the field of regenerative medicine, and should help understand diseases and test new drugs.
"It is a step towards the practical use of reprogrammed cells in medicine, perhaps even eliminating the need for human embryos as a source of stem cells."