The stem cell wars are not over, say leading researchers at Harvard and other universities, who believe that the cloning of human embryos still represents the key to developing effective treatments for an array of horrific diseases.

Although new reprogramming techniques should yield giant advances in researching disease, they remain far too dangerous for actual treatment, rthe scientists say. The induced pluripotent stem cells made by the reprogramming process may never be safe for humans, making it vital to maintain the pace of research on more controversial fronts.