Harvard-affiliated researchers said Tuesday they have begun efforts to create stem cells by cloning human embryos, joining the race among a small group of scientists in this controversial pursuit.
The work at Children's Hospital Boston, the main pediatric teaching hospital of Harvard Medical School, is aimed at eventually creating stem cells for treating blood diseases like sickle-cell anemia, leukemia and other blood disorders.
Dr. George Daley, a leading expert in blood diseases, is overseeing the work at the hospital. Daley, an executive committee member of the Harvard Stem Cell Institute, said he had begun experiments but declined to describe the results of his work so far.
Two other researchers, Douglas Melton and Kevin Eggan, have received approval from a series of review boards to begin similar work, the institute said.
Melton plans to focus on diabetes and Eggan plans eventually to work on neurodegenerative conditions like Lou Gehrig's Disease.
Stem cells can give rise to more specialized cells and tissues, which in turn may be useful for transplant to treat a range of diseases. Through embryo cloning, scientists hope to produce transplant material that is genetically matched to patients, avoiding the problem of rejection.
The University of California, San Francisco, is also pursuing the cloning of human embryos, a goal that some find ethically objectionable.
Hwang Woo-suk of Seoul National University in South Korea caused a sensation in February 2004 he and colleagues claimed to be the first to clone a human embryo and recover stem cells from it. He hit the headlines again last year when he said his lab had created 11 lines of embryonic stem cells genetically matched to human patients.
But the promise came crashing down last December and January when Hwang's university concluded that both announcements were frauds.