Two independent research teams, one American and one Japanese, reported in November 2007 that they had reversed the biological clock on ordinary skin cells, converting them into stem cells capable of forming any of the body's 220 tissue types.
The technique holds particular promise because the resulting cells carry the patient's own genetic blueprint, eliminating the rejection problems that complicate conventional organ transplants. Researchers also saw it as a means of studying how diseases such as diabetes, cancer, and Alzheimer's develop, and of running chemical screens that could speed the path from laboratory to approved drug.
The reprogramming process requires only four genes, making it feasible in a standard laboratory. The current delivery method uses a retrovirus, however, which introduces a mutation risk that rules out therapeutic use for now while leaving the cells available for disease research.
Ian Wilmut, the Scottish scientist who created Dolly, the world's first cloned sheep, announced he would leave embryo-cloning work behind to pursue the new approach. Even so, lead researcher James Thomson of the University of Wisconsin cautioned that embryonic stem cells remain "the gold standard" and should not be set aside.
Historical summary. TurkishPress restated this wire report, first published in November 2007, in its own words.