Pioneer of human cloning resigns after admitting he lied about eggs

The scientist who cloned the first human embryo has resigned in disgrace from an international body after admitting he lied about the source of the eggs used in his experiments.

Professor Woo-Suk Hwang of Seoul National University in South Korea apologised for repeatedly denying that some of the eggs had come from junior members of his own research team. He said he was sorry for making misleading statements when questioned about whether the eggs had been procured unethically from young female colleagues, after the allegations had surfaced in the journal Nature.

Announcing he was stepping down as head of the World Stem Cell Hub "to atone to the public", Professor Hwang appeared downcast and solemn at a press conference yesterday.

"I am very sorry that I have to tell the public words that are too shameful and horrible," he said. "I should be here reporting the successful results of our research, but I'm sorry instead to have to apologise."

Professor Hwang had been fêted around the world when in February 2004 he announced that his team has cloned the first human embryo with a view to developing a new source of stem cells. However, rumours later emerged that some of the eggs from the 16 volunteer donors came from his colleagues which, although not illegal, is considered unethical because the women have felt under pressure to co-operate.

Professor Hwang also said that no money had changed hands with the donors but it emerged this week that a colleague had in fact paid the equivalent of about £1,000 each to some of the women.

"Being too focused on scientific development, I may not have seen all the ethical issues related to my research," Professor Hwang said. "At the time, technology was not as advanced as today and creating one stem cell line required oocytes [eggs]. It was during this time when my researchers suggested making voluntary donations. I clearly turned it down," he said.

But it has now been confirmed that at least two women from his team did donate their eggs. Professor Hwang said that he only become aware of that fact earlier this year.

Professor Hwang's admission came after an American colleague said that he would no longer work with the South Korean scientist because of allegations about unethical behaviour. Professor Gerald Schatten of Pittsburgh University School of Medicine in Pennsylvania began collaborating with him in 1984.

Scientists said that it would not be possible to obtain human eggs in Britain by the unethical methods used by the South Korean team. "In the UK we are fortunate to have had the Human Fertilisation and Embryology Authority in place for 15 years to supervise all research with human embryos," said Professor Ian Wilmut of the University of Edinburgh, who cloned Dolly the sheep.

Peter Braude, a stem cell scientist at King's College London, said it was "an awful shame" that Professor Hwang had been found to have lied. "However, it does not detract from the very real advance that the group has made to the science of stem cell therapy in demonstrating that tailor-made lines can be made relatively easily from eggs if they are donated by young women. The means to achieving this is questionable, not the data."