TOKYO -- A Japanese government-funded laboratory said Friday that it has found "inappropriate handling" of data in a widely heralded stem-cell research paper, but has yet to discover anything that amounts to misconduct.
In an interim report released Friday, the RIKEN research institute said an investigative committee did not find any misconduct in two of the six parts of the paper it is scrutinizing.
RIKEN President Ryoji Noyori, a Nobel laureate in chemistry, said the institute is looking into "significant discrepancies" in the preparation of articles about the research published in January in the scientific journal Nature.
"It may become necessary to demand the withdrawal of the articles," he told a packed news conference in Tokyo.
RIKEN and Nature are investigating allegations of duplicated images of DNA fragments and partial plagiarism.
On Monday, Teruhiko Wakayama, a professor at Japan's University of Yamanashi who was part of the researcher team, said the study -- which had been called "game-changing" when it came out last January -- should be retracted.
Three authors of the paper have agreed to a retraction, said Masatoshi Takeichi, head of RIKEN's Center for Developmental Biology, but a final decision hinges on a consensus of all the authors and the journal itself. Researchers in Boston and Japan conducted the experiments.
The results were seen as a possible groundbreaking method for growing tissue to treat illnesses such as diabetes and Parkinson's disease using a simple lab procedure.
The institute stressed that the aim of the investigation is solely to determine whether there was any misconduct, and not the veracity of the research itself. Takeichi said verification of the results depends on their reproduction by independent researchers.