[Angel]

Harvard University researchers have entered the race to do what Korean scientist Hwang Woo Suk falsely claimed to have accomplished last year: clone a human embryo in the lab to create stem cells genetically matched to a living person.

The Harvard researchers said today they have begun an effort to combine egg cells donated by women with the genetic material of mature cells from adults to create human embryos in a dish.

If they succeed, the scientists will grow the embryos for several days so they can extract stem cells from them. The cells, which can develop into a variety of tissues, may then be transplanted to treat diseases such as sickle cell anemia or diabetes. The cells would be ``patient-specific,'' matched to a person's own genes, avoiding the risk of rejection.

"Researchers must glean what is usable from Hwang's research -- like taking apart a crime scene and putting it back together to figure out the lies from the truth,'' said Christopher Thomas Scott, a medical ethicist at Stanford University, in an e-mail today. ``The group that does it best, and applies the best `art' from other laboratories, will take the turf claimed by the South Koreans.''

At least one other research team in the U.S. is now attempting the same controversial work. Scientists at the University of California-San Francisco, have received the needed approvals from university ethics committees and are ready to try this type of cloning, resuming an effort they abandoned in 2001.

Promising Technology
"It is a promising technology and no one has really succeeded in it,'' said Renee Reijo-Pera, co-director of the university's Human Embryonic Stem Cell Center.

Xiangzhong Yang, a researcher at the University of Connecticut's Center for Regenerative Biology in Storrs who was the first to clone a cow from a skin cell, is also working on this technique. Yang believes that once he has all the needed approvals from ethics boards he will be able to create stem cells using the cloning technique within 1 to 2 years, he said in an interview yesterday.

President George W. Bush has restricted funding for human embryonic stem cell research. The Harvard studies will be entirely privately funded, said Steven Hyman, Harvard provost, on the conference call.

The work is controversial because to accomplish it, human embryos must be created and then destroyed. Many people, including President Bush, object to that on moral grounds.

Moral Objections
Supporters of the research argue that the embryos are destroyed at a stage when they are far from ``personhood'' -- less than 2 weeks old and scarcely bigger than a period at the end of a sentence.

The cloning procedure being attempted at both universities is known as somatic cell nuclear transfer and has been accomplished in numerous animals but not so far in humans. Scientists take a piece of skin from a patient, isolate a cell and remove its nucleus. They then insert that nucleus into an egg cell whose original nucleus has been removed. The resulting embryo is an exact genetic match of the patient.

The cloning technique gained prominence last year when Hwang claimed to have created new stem cells using donor eggs and DNA from patients, a feat that drew headlines and accolades from scientists around the world. Hwang was disgraced when none of the lines he claimed to have created could be found.

The Harvard group decided to announce the beginning of its studies only because of the controversial nature of the work, Hyman said.
'Highly Charged Debate'

"Normally scientists don't discuss their work publicly until it's been peer-reviewed and published,'' he said. ``We're making an exception to our usual policy because of the intense public interest in stem cell science and the highly charged ethical debate over the work.''

Both sets of researchers will be making use of human eggs from different sources. They are now using eggs provided by women who are trying to become pregnant through in vitro fertilization. Some of the eggs, when mated with sperm in a dish, will fail to fertilize. Though they won't lead to pregnancy, they may be suitable for cloning.

Harvard and the University of California-San Francisco also say they will begin soon to seek donations of eggs specifically for use in stem cell research. Ethics rules prevent women who provide eggs from being paid.
Seeking Eggs Donors

"We might guess that women who have families that are afflicted with diseases that we study might step forward,'' said Kevin Eggan, a Harvard stem cell scientist, on the call. ``We'll have to wait and see because it's an entirely new situation.''

Hyman, the Harvard provost, said eight human research committees at the following institutions have reviewed and approved the proposed experiments: Harvard; its affiliates Children's Hospital and Brigham and Women's Hospital; Partners Health Care, the non-profit owner of some Harvard-affiliated hospitals; Boston IVF, a Harvard-affiliated fertility clinic; and Columbia University in New York.

"We're very excited that this research has finally reached the point where we can actually begin experiments,'' said Leonard Zon, a researcher at Children's Hospital in Boston, Harvard's main pediatric teaching hospital, on a conference call. "It has taken just over two years to get to the point where the experiments can proceed.''