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South Korean scandal rocks stem cell community

Woo-Suk Hwang's research is under investigation.

Troubled times: Celebrated cloning researcher Woo-Suk Hwang faces allegations of fraud. Credit: Reuters/Kim Kyung-Hoon

More than a month after South Korean cloning star Woo-Suk Hwang admitted to lying about the source of eggs used in his research, allegations continue to surface about the scientific accuracy and ethics of his landmark papers.

It's going to have a chilling effect on the scientific community. Kevin Eggan, Harvard University

As Seoul National University and scientific journals try to sort out the truth, researchers are grappling with the potential ramifications. “It's going to have a chilling effect not just on the public debate [about stem cell research] but also on the scientific community,” says Kevin Eggan, a stem cell researcher at Harvard University.

Hwang, a veterinarian, became famous in 2004 for establishing the first stem cell line from a cloned human embryo (Science 303, 1669–1674). A few months later, an article in Nature suggested that two junior members of Hwang's team—both of whom were authors of the paper—had donated eggs, a crucial resource in the experiment (429, 3; 2004).

Hwang dismissed the report as based on a language misunderstanding and, over the next year, continued to deny the allegations (Nat. Med. 11, 464; 2005). In November, he shocked the world when he admitted that the two women in his laboratory had donated the eggs.

Soon after, his 2005 paper, which reported 11 stem cell lines tailored to diseased patients, (Science 308, 1777–1783), came into question when corrections to the data fueled rumors that some of the results might have been fabricated.

The second author on the paper, MizMedi hospital's Sung-Il Roh, told reporters that Hwang had fabricated data. Hwang later asked Science to retract the paper, but insists that the problems are a result of small errors in management rather than of scientific misconduct. He says many of the cell lines have been destroyed, but promised to prove the authenticity of his work by thawing some remaining cell lines.

Hwang is now fighting an uphill battle to regain credibility. His once-bustling lab in the hilly Seoul National University campus is roped off. Access by team members has been restricted and closed circuit televisions monitor the lab.

There is some evidence, still unaddressed, that one of the donors might have felt under pressure to give their eggs. According to Roh, a fertility expert who collected the eggs for Hwang, one laboratory member donated her eggs to make up for the hundreds of eggs she had wasted early in the experiment. Roh, who says he tried to dissuade her from donating, quoted her as saying, “If I don't sacrifice, the project can't succeed.”

An investigation by the ministry of health concluded in November that the donations were voluntary. But determining whether there was any pressure from Hwang might require more information. “The egg donor and lab scientist have conflicts of interest,” says Seoul National University's Ock-Joo Kim, head of the Korean Association of Institutional Review Boards.

Kyu-Won Jung, a bioethicist at Hanyang University who helped Hwang's group revise its informed consent protocols for the 2005 paper, says the possibility of pressure from senior researchers has to be carefully weighed. “If I were the IRB member who should decide the approval, I would not approve the donation by a lab member,” he says.

A resolution might be in the offing. The National Bioethics Committee is looking into Hwang's donor recruitment procedures as well as the role of the Internal Review Board that oversaw his experiment. Seoul National University is also investigating the allegations. That inquiry might include DNA tests that would determine whether the cell lines are true clones.

As Nature Medicine went to press, scientists were also questioning the seminal 2004 paper that demonstrated the ability to create stem cell lines from cloned human embryos. “I think at this point, we can assume nothing,” says Eggan. “One can never really know how far back an indiscretion goes.”

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Korea's stem-cell stars dogged by suspicion of ethical breach

Profile: Woo-Suk Hwang

Where now for stem-cell cloners?

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Science magazine's statement on Hwang

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Cyranoski, D. South Korean scandal rocks stem cell community. Nat Med 12, 4 (2006).

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