Scientists have for the first time used cloning to create human embryos that live long enough in a laboratory dish to have their stem cells harvested. The feat could set the stage for physicians to produce cells and tissues, tailored to a patient's genetic identity, that can treat a wide variety of human illnesses. The accomplishment also provides a road map for how to clone a person, an even more divisive undertaking.
The new work, performed in South Korea, represents "a major advance in stem cell research . . . . It could help spur a medical revolution as important as antibiotics and vaccines," says Robert Lanza of Advanced Cell Technology (ACT), a company in Worcester, Mass., that's also investigating the promising stem cell strategy dubbed therapeutic cloning.
"However, now that the methodology is publicly available," Lanza adds, "I think it is absolutely imperative that we pass