The science world was abuzz in late January, when researchers from the RIKEN Center for Developmental Biology, in Japan, announced that they had devised a simple way of forcing adult cells to become embryonic-style stem cells. Embryonic stem cells have the remarkable ability to transform into any other cell type, so finding an easy way to make regular cells revert to this state could one day allow physicians to repair damaged cells and grow new organs. But an unexpected announcement from one of the study's authors on Monday is now putting the study's findings into question, reports The New York Times, and many scientists — including the author himself — are calling for its retraction.

The study, published in the journal Nature, demonstrated the use of a new technique called stimulus-triggered acquisition of pluripotency (STAP). The method is based on the idea that mature adult cells react to severe trauma — in this case, oxygen starvation or acidic conditions — by reverting to an embryonic-like stem cell state. Yet now that Teruhiko Wakayama, a developmental engineer at the University of Yamanashi, is questioning his own study's results, the future of this technique is becoming increasingly uncertain.

Others were unable to replicate the findings

Upon publication, the paper was an immediate media success and many prominent scientists expressed their enthusiasm. But skepticism slowly set in as other laboratories were unable to replicate the Japanese team's findings. As a result, the team released a series of "essential technical tips" to help scientists through the procedure, telling Nature News that the procedure required special care. Finally, a series of allegations starting popping up on various science blogs about some of the paper's images and content. It appeared that one of the bar graphs, as well as some of the wording employed in the paper, had been duplicated from co-author Haruko Okobata's previous work. Okobata, a 30-year-old biologist at RIKEN, rose to fame in Japan following the study's publication.

Okobata has remained silent on the issue

Wakayama is now calling for the paper's retraction. "To investigate the study's validity, we must first retract it, collect the right data and photos, and try to prove again that the study was right," he told NHK, Japan's public broadcaster. "I think an outside investigation would also be important." So far, Okobata has remained silent on the issue.

Nature Publishing Group, the company that owns the journal in which the study was published, told Nature News in February that they were investigating the allegations. But the company has yet to address Wakayama's own call for retraction.