A young researcher who shot to fame in scientific circles when she published an apparently radical and simple way to create stem cells has been found guilty of misconduct by a committee charged with investigating her work.
Haruko Obokata, at the Riken Centre for Developmental Biology in Kobe, announced the breakthrough in January in two articles published in the scientific journal Nature, but the discovery was thrown into doubt after researchers elsewhere failed to replicate her work.
The ruling has not settled the debate over whether her breakthrough was real, though. In a bizarre twist in an already convoluted story, the committee's ruling against Obokata came moments before an independent researcher claimed to have succeeded in making the cells using a slightly different procedure.
Much of the scrutiny of Obokata's claims played out on science websites where researchers pointed to several discrepancies in her work, including images that looked manipulated, and text that appeared to have been plagiarised. The doubts led to a split among the authors of the papers, with one, Teruhiko Wakayama, calling for a retraction until the research had been thoroughly checked.
Obokata led the studies into so-called Stap (stimulus-triggered activation of pluripotency) cells, in which she claimed to have made versatile stem cells that could grow into any tissue by immersing blood cells from mice in a weak acid solution. But other researchers co-authored the papers, including Prof Charles Vacanti at Harvard Medical School in Boston. The research promised to revolutionise the field of stem cell research because the procedure was so simple.
The growing storm over Obokata's research prompted Riken to launch an investigation into her work. At a press conference in Japan on Tuesday, the committee said it had found evidence of falsification and fabrication – offences that constitute research misconduct. One image of DNA was spliced together from two others. "The manipulation was used to improve the appearance of the results," said the head of the committee, Shunsuke Ishii. Obokata counters that she only wanted to make the image clearer, and that it had no bearing on the results. A second offence involved reusing data apparently from her doctoral thesis.
Obokata did not attend the press conference, but issued a statement in which she said: "I am filled with feelings of indignation and surprise." According to Science journal, she intends to appeal the judgment. The magazine quoted the committee as saying: "Dr Obokata's actions and sloppy data management lead us to the conclusion that she sorely lacks, not only a sense of research ethics, but also integrity and humility as a scientific researcher."
But the committee's final report came as another scientist seemed to validate Obokata's work, at least in part. The head of stem cell research at the Chinese University of Hong Kong, Kenneth Ka-Ho Lee, posted details of his success on the ResearchGate website, where he had previously live-blogged his failure to make the cells. Prof Lee's experiments were based on an updated procedure drawn up by Vacanti at Harvard.
The investigating committee was not asked to rule on whether Obokata's procedure worked, nor whether her articles should be withdrawn. But the president of Riken, Ryoji Noyori, said he wanted the papers retracted if the committee's judgment was upheld at appeal.
The saga has left some scientists uneasy about the research, but also about how Obokata has been treated. The director of the Centre for Stem Cells and Regenerative Medicine at King's College London, Prof Fiona Watt, said: "I'm outside this field but the whole process of the investigation and the conclusions have come out very quickly. I don't condone fradulent research in any way, but I do think that senior scientists have a duty of care to their younger colleagues, and I hope that Dr Obokata will not be treated as a scapegoat."
A Nature spokesperson said the journal's editors were investigating the papers for themselves. "Nature has now been provided with the details of the Riken investigation and is carefully considering them. We cannot comment while we are doing so, but we do expect to be able to provide a further comment in the near future," the spokesperson said.
"We don't comment on individual instances but, in general, all retractions are considered on a case-by-case basis. In cases where not all of the authors agree on a retraction, Nature evaluates whether the evidence available supports the main conclusions of the paper. We may decide to retract in cases where the authors cannot provide evidence to support the main conclusions of the paper. In such cases, if some authors still disagree with the retraction, we note the dissenting authors in the retraction notice."
• This article was amended on 2 April 2014. An earlier version referred to the peer-reviewed Science journal as a magazine.