TOKYO, Nov. 24 - The South Korean researcher who won world acclaim as the first scientist to clone a human embryo and extract stem cells from it apologized Thursday for lying over the sources of some human eggs used in his work and stepped down as director of a new research center.
Hwang Woo Suk at a news conference in Seoul announcing his resignation as head of his research center.
Hwang Woo Suk, the South Korean stem cell researcher who won world acclaim as the first scientist to clone a dog, Snuppy.
After months of denying rumors that swirled around his Seoul laboratory, the researcher, Dr. Hwang Woo Suk, confirmed that in 2002 and 2003, when his work had little public support, two of his junior researchers donated eggs and a hospital director paid about 20 other women for their eggs.
On several earlier occasions, he had said that he did not use eggs harvested from subordinates and that no one was paid for egg donations.
"Being too focused on scientific development, I may not have seen all the ethical issues related to my research," Dr. Hwang, a veterinarian by training, told a news conference in Seoul on Thursday. "I should be here reporting the successful results of our research, but I'm sorry instead to have to apologize." He said the staff donations had taken place without his knowledge.
"We needed a lot of ova for the research, but there were not enough ova around," he said. "It was during this time when my researchers suggested making voluntary donations. I clearly turned it down."
He said he later discovered they had donated eggs under false names in 2003.
Although the egg donations by the junior researchers were not considered a legal or ethical violation, critics say that in the strict hierarchy of a scientific laboratory in a Confucian society like South Korea, junior members often feel great pressure to please their superiors. Under international medical ethics standards, researchers are warned against receiving eggs from members of their own research teams who are deemed to be in a dependent relationship.
Payment for eggs was not illegal in 2003, but it was banned last January by South Korean law.
Dr. Hwang and his team's production of stem cells from cloned human embryos in 2004 was considered a major step toward eventually treating conditions like Alzheimer's disease and spinal cord injuries. But the human eggs ethics controversy may give ammunition to his opponents, who warn that his work could lead to human cloning.
His team also cloned a dog, an Afghan named Snuppy, who appeared on the cover of Time magazine, which declared his team's feat this year's most amazing invention.
Dr. Hwang's fall from grace is a blow to South Korea, where he had become the modern, high-tech face that the nation seeks to project to the world. He appeared in national promotional campaigns. Korean Air recently declared him a "national treasure," giving him and his wife first-class tickets for a decade.
Only last month, his research center, the World Stem Cell Hub, opened with $132 million from the South Korean government. Plans were announced to open satellite cloning centers in San Francisco and London. On Thursday, as part of what he called "repentance," Dr. Hwang resigned as head of the new center.
His world reputation is now expected to suffer a major dent over his admissions that he lied to an international scientific journal over eggs obtained in what many see as an ethically murky manner. The scandal may also cloud plans to expand research to the United States, but Dr. Hwang said he planned to continue his laboratory work.
Two weeks ago, on Nov. 12, widespread murmuring about the ethics of some of the human-egg gathering flared into the public eye when Gerald P. Schatten of the University of Pittsburgh, Dr. Hwang's American partner, announced that he was severing relations with him.
The abrupt disintegration of the partnership was surprising because the two scientists had collaborated for 20 months and reported important findings together. Dr. Schatten's stated reasons for the rupture seemed comparatively minor.
In a written statement, on which he has since refused to elaborate, he said his decision was grounded solely on concerns regarding egg donations in Dr. Hwang's research.
