Stem cells have excited huge interest over the past decade as it holds out the possibility of reversing cancer, diabetes, Alzheimer's and other regenerative diseases.

However, the research has been controversial and sapped by opposition from religious conservatives, who argue that research on embryos – the prime source of stem cells so far – destroys human life.

In the new studies, published by the British-based journal Nature, the research raises the practical prospect for the first time of developing wide-ranging "spare part" stem cell treatments without having to destroy human embryos.

Lead researcher Keisuke Kaji from the Centre for Regenerative Medicine at the University of Edinburgh, Scotland, said the breakthrough could end the need for human embryos as a source of stem cells.

"This new method will advance the field of regenerative medicine, and should help understand diseases and test new drugs," Kaji said.

Reprogramming the skin cells allows them to assume the properties of stem cells obtained from embryos with the potential to become virtually any kind of body tissue, the Daily Telegraph newspaper reported on Monday. The technique was developed both in mouse and human skin cells.

Previously it was only possible to create these "induced pluripotent stem" (iPS) cells, as they are known, using viruses to insert the four genes that carry out the reprogramming.

The new approach not only avoids the use of viruses, but allows the transformational genes to be removed after their job is done to prevent them causing future damage, the British daily said.

Researcher can now look more seriously at the prospect of using iPS cells to produce replacement tissue for patients with degenerative and currently incurable diseases.

Made from a patient's own skin cells, they would also not be limited by the usual problem of immune system rejection, it said.

Andras Nagy, from the University of Toronto, combined his research of cell programming to make the new breakthrough with Kaji.