--- description: A leading Japanese scientist who oversaw a discredited study on stem-cell creation has committed suicide. title: Stem-Cell Research: Japanese Scientist Yoshiki Sasai Commits Suicide image: https://static.time.com/v3/assets/bltea6093859af6183b/bltbe29e6ef306e6c69/69869e81cd6848034c095f10/japan-scientist-dead_wong.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  * [Science](/section/science/) ## Science Update your preferences in [Account Settings](/account/preferences/) Close # Top Japanese Scientist Who Co-Authored Discredited Stem-Cell Study Commits Suicide by [Melissa Hellmann](/author/melissa-hellmann/) ## Melissa Hellmann Update your preferences in [Account Settings](/account/preferences/) Close Aug 6, 2014 6:38 AM CUT  Yoshiki Sasai, deputy chief of the RIKEN Center for Developmental Biology, speaks during a press conference in Tokyo on April 16, 2014\. Police said Sasai, 52, was found dead on Tuesday, Aug. 5, 2014. Yoshiki Sasai, deputy chief of the RIKEN Center for Developmental Biology, speaks during a press conference in Tokyo on April 16, 2014\. Police said Sasai, 52, was found dead on Tuesday, Aug. 5, 2014.AP by [Melissa Hellmann](/author/melissa-hellmann/) ## Melissa Hellmann Update your preferences in [Account Settings](/account/preferences/) Close Aug 6, 2014 6:38 AM CUT A top Japanese scientist who oversaw and co-authored a controversial stem-cell study has [committed suicide](http://www.independent.co.uk/news/science/japanese-stem-cell-scientist-yoshiki-sasai-found-dead-in-apparent-suicide-9650050.html "undefined") by hanging, authorities said on Tuesday. Yoshiki Sasai, 52, was found in a research institution next to his workplace by a security guard on Tuesday morning and was pronounced dead at a hospital two hours later. Sasai was deputy director of the prestigious RIKEN Center for Developmental Biology, and supervised a study by lead author Haruko Obokata that was published in the journal _Nature_ earlier this year. Obokata claimed to have found a highly innovative new method for creating stem cells, but when the method could not be replicated, a probe was launched and it was found that parts of the study had been plagiarized. The paper was withdrawn from _Nature_ in July, following months of dispute about its veracity. [According](http://online.wsj.com/articles/japanese-stem-cell-scientist-yoshiki-sasai-is-dead-1407206857 "undefined") to the _Wall Street Journal_, Sasai maintained that he was brought into the project at a late stage. He consistently expressed remorse for not keeping a closer eye on the research, while continuing to argue that parts of the study held evidence of a genuine breakthrough. Phil Campbell, editor in chief of _Nature_, issued a statement calling Sasai’s death a great loss to the scientific community. “Yoshiki Sasai was an exceptional scientist, and he has left an extraordinary legacy of pioneering work across many fields within stem cell and developmental biology,” Campbell said. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/3084494/japanese-scientist-yoshiki-sasai-suicide-stem-cells-study-haruko-obokata/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/3084494/japanese-scientist-yoshiki-sasai-suicide-stem-cells-study-haruko-obokata/"},"headline":"Top Japanese Scientist Who Co-Authored Discredited Stem-Cell Study Commits Suicide","datePublished":"2014-08-06T06:38:15.000Z","dateModified":"2026-02-21T09:31:24.893Z","description":"Death is mourned as huge loss to scientific community","url":"https://time.com/3084494/japanese-scientist-yoshiki-sasai-suicide-stem-cells-study-haruko-obokata/","keywords":["Suicide","Japan","Science topic"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/bltbe29e6ef306e6c69/69869e81cd6848034c095f10/japan-scientist-dead_wong.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Melissa Hellmann","jobTitle":null,"url":"https://time.com/author/melissa-hellmann/"}],"articleSection":"Science","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/bltbe29e6ef306e6c69/69869e81cd6848034c095f10/japan-scientist-dead_wong.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Yoshiki Sasai","caption":"Yoshiki Sasai","creditText":"AP","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/science/","name":"Science"}},{"@type":"ListItem","position":2,"item":{"@id":"https://time.com/3084494/japanese-scientist-yoshiki-sasai-suicide-stem-cells-study-haruko-obokata/","name":"Top Japanese Scientist Who Co-Authored Discredited Stem-Cell Study Commits Suicide"}}]}] ```