The suicide of Yoshiki Sasai, a globally renowned researcher and co-author of controversial stem cell research, could have been avoided if the Riken research institute had implemented reform measures proposed in June and had accepted his resignation earlier in the year, the former head of an independent panel said Wednesday.

"If Sasai was able to quit Riken when he offered his resignation as deputy director in March, there would possibly be no trouble" now, said Teruo Kishi, who chaired the reform panel that proposed the measures for the institute, including the Riken Center for Developmental Biology in Kobe.

"And if Riken had replaced Sasai in accordance with our proposal (which called for all executives at the Kobe facility, including Sasai, to be replaced), this wouldn't have happened," Kishi said in a telephone interview with The Japan Times, lamenting the loss of Sasai, who he described as "a gem."