This feels a bit like deja vu.
Scientists report a major breakthrough in human stem-cell research. And then just a week later, the findings come under fire.
Biologists at Oregon Health & Science University said May 15 that they had cloned human embryos from a person's skin cell.
Researchers have been trying to do this for more than a decade. Many scientists in the field were heralding the announcement as discovery of the Holy Grail because now they could make personalized stem cells for treating an array of diseases.
But several images in the paper aren't quite right, a commenter said Wednesday on the website PubPeer.
Specifically, three pairs of photos are duplicated and then labeled as different results. There are also some questions about data demonstrating that the scientists had created stem cells.
The lead author on the study, Shoukhrat Mitalipov, staunchly defended his findings Thursday to the journal Nature. "The results are real, the cell lines are real, everything is real," he said.
Mitalipov claims the problems in the paper were innocent mistakes made because he rushed to publish the findings in the journal Cell.
Right now, the editorial team at Cell supports the study and Mitalipov's claims.
"Based on our own initial in-house assessment of issues raised ... it seems that there were some minor errors made by the authors when preparing the figures for initial submission," Cell's editor Emilie Marcus said on Facebook. "While we are continuing discussions with the authors, we do not believe these errors impact the scientific findings of the paper in any way."
The journal reviewed and accepted the paper four days after receiving it. The paper was then published online 12 days later. Typically, this process takes at least two months and can even last years.
With such a fast turnaround time, some scientists are being careful not to jump to conclusions. "I expect the errors above were also due to the rush to publish." Robin Lovell Badge, at the MRC National Institute for Medical Research in London, told Nature. "The authors should be given a chance to answer and correct mistakes,"
But others think the team should have been more diligent, especially given the past problems in the field.
Back in 2005 and 2004, South Korean veterinarian Hwang Woo-suk published two papers claiming to have cloned human embryos. By early 2006, a committee in Seoul concluded that Hwang fabricated the data in both studies and the journal Science retracted both papers.
"The four-day review process was obviously inadequate," Arnold Kriegstein, of the University of California, San Francisco, told Nature, referring to Mitalipov's study. "It's a degree of sloppiness that you wouldn't expect in a paper that was going to have this high profile. One worries if there is more than meets the eye and whether there are other issues with the work that are not as apparent."
Scientists will know soon enough. It's rather straightforward to confirm Mitalipov's results. If the embryos were indeed created by putting the nucleus of a skin cell into a donor egg, the stem cells will have the exact genetic fingerprint of the skin plus a tiny bit of DNA left over from the egg (specifically, its mitochondria).