Reprogrammed cells have apparently cured sickle cell anaemia in mice, a development which scientists say proves that clinical applications of the new technique are feasible. Researchers at the Whitehead Institute for Biomedical Research, in Cambridge, Massachusetts, published their results in the journal Science. "This demonstrates that iPS [induced pluripotent stem] cells have the same potential for therapy as embryonic stem cells, without the ethical and practical issues raised in creating embryonic stem cells," says leading stem cell scientist Rudolf Jaenisch. "All the parameters we can measure are now normal. The mice are cured."

However, the scientists cautioned that there are many hurdles to be overcome before human therapies are available. At the moment, the iPS cells are likely to cause tumours, although they are confident that they can solve this problem. Jaenisch, who was a strong supporter of therapeutic cloning, insists that it is important to continue working with embryos. "All the progress in this field was only possible because we had embryonic stem cells to work with first," he says. "We need to make more ES cells and really define which are going to be the best ones for different applications." ~ Washington Post, Dec 7; Sydney Morning Herald, Dec 7