A stem-cell scientist branded a cheat for faking research has been commended for achieving a breakthrough discovery, albeit by accident.

The latest twist in the extraordinary story of Woo Suk Hwang, the disgraced South Korean, came yesterday as American scientists published analysis that concluded he should be credited with a world first. However, they said that his failure to recognise his own breakthrough – using a technique that takes its name from the virgin birth – cast further doubt on his abilities and integrity.

According to a US study published in the journal Cell Stem Cell, a line of human embryonic stem cells created by Professor Hwang, which he claimed fraudulently to have cloned, were in fact the first to have been made by a different process that has significant medical potential. Analysis of the cells has shown that they were derived by parthenogenesis, a method of reproduction by which unfertilised eggs start to divide to form embryos, as if they had been fertilised by sperm.

Though Professor Hwang’s team appears to have done this by accident, the achievement is still important because parthenogenesis is itself promising as a source of stem cells for research and therapy.

Parthenogenesis, which takes its name from the Greek words for “virgin birth”, is a method of reproduction used by all fungi, most plants and many animals, including lizards, bees, corals and some birds and fish. Mammals cannot produce offspring in this way and it is extremely difficult to induce parthenogenesis in the laboratory.

A handful of human embryos have been made by parthenogenesis before, including by a team led by Paul de Sousa, at the Roslin Institute near Edinburgh, but these have always died before reaching the stage at which stem cells could be extracted.

Yesterday’s revelation is unlikely to rehabilitate the scientific reputation of Professor Hwang, who was hailed as a national hero in South Korea in 2004, when he published details of what were purported to be the world’s first stem cells made from cloned human embryos. Stamps were issued commemorating his research and he was awarded the title of Supreme Scientist.

In 2005 it emerged first that his cloning experiments had been conducted using eggs donated by junior staff of his own laboratory – a serious breach of ethics because of potential for coercion – and then that his results had been faked. He was found guilty of scientific fraud, dismissed by Seoul National University and indicted for embezzlement of some of the extensive government funding invested in his research. His disgrace was viewed widely in South Korea as a national humiliation.

George Daley, of Children’s Hospital Boston and the Harvard Stem Cell Institute, who led the new research, said that while the isolation of parthenogenetic stem cells would have been an important achievement, Professor Hwang’s attempt to pass the cells off as clones made it “a woeful case of misconduct”.

Professor Hwang had claimed that his stem cells had been made by somatic cell nuclear transfer, the cloning process used to create Dolly the sheep. It involves inserting the nucleus of an adult cell into an egg from which nuclear DNA has been removed, then coaxing it to divide into an embryo.

Such cloned cells have medical value as research tools for modelling diseases and may in the long term be useful therapeutically to make genetically matched replacement tissue for treating conditions such as diabetes and Parkinson’s disease.

Cloned cells and parthenogenetic cells, however, have distinctive genetic signatures, and Professor Hwang’s line has now been tested for these by Dr Daley’s team. “We know now that the Koreans’ first supposed nuclear transfer-derived stem cell line was actually derived from the woman’s egg alone,” Dr Daley said.

Even so, the proof that it is possible to make human stem cells by parthenogenesis is significant. Dr Daley said that it might be possible to create banks of stem cells in this way, which could be genetically screened and matched to patients whose immune systems would not reject them.

He believed that Professor Hwang created parthenogenetic embryos by accident and lacked the tools to test them properly to show their origins. It remains impossible to tell whether or not he suspected his mistake, but lied about the cells anyway.

Dr Daley said: “We just don’t know, and this is one of the curious and provocative questions that may go unanswered in the history of this debacle.”

Pioneer’s rise and fall

— Eight years ago a dairy cow called Yeongrongi was born, and Hwang Woo Suk begin his ascent to the top of the South Korean scientific aristocracy. Professor Hwang claimed that Yeongrongi was a clone, at the time the fifth such animal to be created

— Two months later he created the sixth and – with what his critics would claim was typical media awareness – let the President of Korea name it

— By the time of his 2003 claim that he had cloned a BSE-resistant cow, scientists were beginning to question whether he had evidence to back up his work

— Professor Hwang later gained international scientific stardom by publishing two papers in Science that purported to show that he had cloned a human embryo

— In 2005 the Korean Government declared him “Supreme Scientist” and gave his research group millions of pounds

— By now Professor Hwang’s achievements appeared to more than justify his status. His researchers went on to create the first cloned dog – an Afghan hound called Snuppy, below – in 2005, and he sat on South Korea’s main scientific advisory body

— His fall from grace was even more rapid than his rise. A documentary claiming that he had unethically used eggs from female research assistants initially infuriated the public. But the follow-up investigations showed – far more significantly – that he had fabricated data in his Science papers

— Professor Hwang was charged with fraud and embezzling money from those who backed his research, and had no choice but to resign

Sources: Times archive, Time East Asian Science and Technology journal, agencies

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