Testing of cells derived using the controversial STAP technique indicates that those cells don't match the mice from which they were supposed to have been derived, the Nature News Blog reports.
The STAP, or stimulus-triggered acquisition of pluripotency, method was published earlier this year in Nature by Riken's Haruko Obokata, but those papers quickly aroused suspicions. An investigation by Riken concluded that Obokata was guilty of research misconduct, which she denied, attributing the errors to her inexperience.
Yamanashi University's Teruhiko Wakayama, one of the co-authors on the STAP papers, performed some genetic analyses on some cell lines that he derived using the STAP approach back in March, the Nature News Blog reports. Some of these, he found, didn't match the mice from which they were supposed to have been generated, indicating that there may have been contamination. However, he didn't find a problem with the lines reported in the Nature papers, though he sent those and other lines to an independent, and unnamed, lab for further examination.
Japanese media, the Nature News Blog says, is reporting that those independent tests have found that none of the STAP cell lines match the mouse strains they were supposed to be from, "calling into question whether the STAP phenomenon has ever been demonstrated."
The Nature papers also may not be long for the world of scientific literature. Last week, the Nature News Blog said that Obokata agreed to retract one of the two STAP papers, and now ScienceInsider says she has consented to retract both papers.
Still, ScienceInsider adds that that won't be the end of the ongoing saga as Riken is working on determining whether the STAP phenomenon exists and as some critics are asking how the flawed papers were published in the first place.
"The science of the two papers was rigorously, robustly peer-reviewed as part of our usual editorial procedures. Any inaccuracies in the presentation of data that may have come to light since the peer review are being investigated," a spokesperson from Nature tells ScienceInsider.