A Japanese scientist involved in a scandal over discredited stem cell research has been found dead at his laboratory in an apparent suicide.
Prof Yoshiki Sasai, 52, was cleared of direct misconduct by an investigation, but faced criticism for his oversight.
Scientists around the world have expressed regret at losing a renowned researcher and concern at the “witch-hunt” that followed the revelations.
The 52-year-old professor, well known for his work turning stem cells into other types of cells like eye and brain tissue, was found by a security guard at RIKEN’s Centre for Developmental Biology in Kobe, western Japan.
Prof Sasai, the centre’s deputy chief, was widely respected in the scientific community. But earlier this year two studies that he supervised caused controversy, after other scientists failed to replicate the results.
The two papers, both published in the journal, Nature in January 2014, had suggested that stem cells could be produced from normal adult cells by dipping them into acid for a 30-minute shock period.
These “STAP” cells (stimulus-triggered acquisition of pluripotency) held great promise for both developmental biology and medical science.
But the widely reported findings were too good to be true, attracting scepticism and, eventually, claims of scientific fraud.
The work was investigated by RIKEN and retracted in July, amid concern that some of the results had been fabricated.
Although the study’s first author, Dr Haruko Obokata, was found guilty of misconduct, Prof Sasai was cleared of direct involvement.
He was criticised, however, for his supervision of Dr Obokata and for not spotting inconsistencies in the publications.
