Scientists have found a new and safer way to generate induced pluripotent stem cells (iPS), which are cells that have all the qualities of embryonic stem cells, but they are produced from adult cells, an alternative to the technique which involves taking human embryos. Just like the ordinary stem cells, the new induced pluripotent stem cells could be cultured into any desired tissue, from heart muscle cells, and blood cells to brain cells.

The problem was that iPS cells creation involved the use of retroviruses, which can integrate into the genome and pose a risk of cancer. But the new research has reportedly eliminated iPS cells’ tendencies to become cancerous.

For the study, Konrad Hochedlinger of Massachusetts General Hospital and Harvard Medical School in Boston and colleagues used a much more harmless virus called an adenovirus to carry into the cells the four transformative genes, called Oct4, Sox2, Klf4 and c-Myc. Adenoviruses do not insert their viral DNA into a cell’s chromosomes. "The adenovirus doesn't integrate permanently, so the cells aren't altered genetically," said Konrad Hochedlinger, geneticist at Harvard Stem Cell Institute in Cambridge, Mass., and lead author of the paper.

Though demonstrated only in mice so far, the result marks an important step forward in stem cell research and in the so-called regenerative medicine by developing a safer way of obtaining stem cells from common skin cells without using harmful viruses that can cause cancer.

The findings of the study were published in the Sept. 25 online edition of the journal Science.