The prospect of transforming a patient's own skin cells into a life-saving therapy to treat incurable conditions such as Parkinson's disease has come a step closer.
Scientists have devised a safe way of producing stem cells for transplant surgery from skin cells without using either human embryos or the potentially harmful viruses normally used to transfer the special genes for transforming ordinary skin cells into stem cells.
Last year, scientists demonstrated that they could genetically engineer embryonic stem cells by introducing a handful of genes into a skin cell with the help of a virus. But the resulting stem cells could not be used in medicine because of the fear that viral genes may also be introduced into a patient. The latest study, however, has shown it is possible to produce these so-called induced pluripotent stem (iPS) cells without using viruses and without introducing any foreign genes into the embryonic stem cells, by using a different genetic engineering technique, according to Professor James Thomson of the University of Wisconsin-Madison, whose study is published in the journal Science.
Many scientists believe iPS cells, which are made without the need for human embryos, bypass many of the ethical and moral objections to using embryonic stem cells. Researchers are still working on ways of guaranteeing their safety if they are ever used in transplant surgery.
Marion Zatz of the US National Institute of General Medical Sciences said: "This latest discovery by Thomson's group of a new method for generating iPS cells without inserting viral vectors into the cells' genetic material is a major advance toward safely reprogramming cells for clinical use."