WHILE therapeutic cloning is storming ahead, hopes that adult stem cells could be as fertile a source of replacement tissue as embryonic stem cells have taken a blow. Studies apparently showing that stem cells taken from adults can develop into a variety of tissues may have been flawed.
This warning comes from two groups, one led by Austin Smith of the University of Edinburgh and the other by Edward Scott of the University of Florida in Gainesville. They found that rather than forming a range of tissue types by themselves, adult stem cells may be forming abnormal hybrids with embryonic…
