The retraction notice from Riken's Haruko Obokata and her colleagues says that "[s]everal critical errors have been found in our Article and Letter" and that a subsequent investigation of those errors by Riken found evidence of research misconduct.
"The STAP technology, indeed, sounded too good to be true," Dusko Ilic, from King's College London, tells Reuters. "I hoped that Haruko Obokata would prove at the end all those naysayers wrong. Unfortunately, she did not."
In an editorial, Nature also argues that it couldn't have caught the errors, Retraction Watch's Ivan Oranksy writes.
"We at Nature have examined the reports about the two papers from our referees and our own editorial records," the editorial notes. "Before publishing, we had checked that the results had been independently replicated in the laboratories of the co-authors."
Still, the journal says the incident has highlighted flaws in publishing procedures.
"We — research funders, research practitioners, institutions and journals — need to put quality assurance and laboratory professionalism ever higher on our agendas, to ensure that the money entrusted by governments is not squandered, and that citizens' trust in science is not betrayed," it adds.