Scientists have succeeded in turning embryo cells into blood cells raising the prospect of creating blood in the laboratory.
The breakthrough could ultimately provide an alternative source of blood for transfusions and even bone marrow to help treat patients with leukaemia and other cancers. Manufactured blood could also help to prevent the body from rejecting transplanted organs
Central to the discovery are stem cells - the most basic form of cell found in human embryos - which have the potential to turn into any tissue in the body.
Work in this field has caused massive ethical controversy on both sides of the Atlantic. Haematologist Dr Dan Kaufman of the University of Wisconsin headed the study,which is published today in the Proceedings of the National Academy of Sciences. "We now accept that stem cell research will eventually lead to treatments for a variety of serious conditions", he said.
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