A young female scientist accused of fabricating data made a tearful apology live on Japanese television Wednesday for "mistakes" in her research, but insisted her ground-breaking conclusions on stem cells were accurate.
Haruko Obokata, 30, blamed her youth and inexperience for errors in her methodology, but said she had managed to create the building-block cells capable of growing into the specialised cells of the brain, liver, heart or kidneys.
"I apologise with my whole heart to my co-authors... and many others for causing trouble because of my insufficient efforts, ill-preparedness and unskilfulness," a visibly shaken Obokata told a press conference.
"To many people there may be too many unbelievable mistakes, but that does not affect the conclusion," she said.
Obokata was feted as a modern-day Marie Curie after unveiling research that showed a simple way to re-programme adult cells to become a kind of stem cell.
So-called Stimulus-Triggered Acquisition of Pluripotency (STAP) cells were hailed as a breakthrough that could provide a ready supply of the base material for much-needed transplant tissue, at minimal cost.
Campaigners said it represented a leap forward in the fight against degenerative diseases.
If the science was important, Obokata's profile—a young woman in a world dominated by middle-aged men—proved irresistable to Japan's media.
Journalists were beguiled by eccentricities that included her insistence on wearing a housewife's apron in the laboratory, instead of a white coat.
But within weeks of her paper being published in the prestigious journal Nature, questions began to emerge, with fellow scientists saying they could not replicate her results.
The respected Riken Institute, which sponsored the research, launched an inquiry and declared last week that the study was flawed.
This "amounts to phoney research or fabrication" by Obokata, Shunsuke Ishii, head of Riken's probe committee, told a press conference after it was revealed Obokata had cut-and-pasted illustrations used in other studies.
On Wednesday she accepted that the way she had presented the data was not right, but insisted it had been done for cosmetic reasons and not to alter the outcome.
"I thought there would be no problem as long as I could show the results properly," she said Wednesday.
"People say I should retract the papers, but doing so will mean that the outcome of my research is completely wrong. I can't say that to the world because the outcome is right."
Obokata on Tuesday submitted a formal complaint to Riken over its declaration that the study was bogus, demanding it reverse its decision and stand by her work.
Kyodo News reported that Riken's rules require that an investigative panel scrutinise her objection and give its findings within 50 days.
If it finds against her, she will be "disciplined" by the institute, which said this week it was launching a year-long study to establish if there was any truth in Obokata's findings.
On Wednesday the young scientist choked back sobs during a two-and-a-half-hour press conference carried on at least two television channels, in which she insisted: "STAP cells do exist. I successfully made STAP cells at least 200 times."
She said she did not believe her study should be retracted and she hoped to announce new research showing "a certain recipe" to create the cells.
"If there is any future for an inexperienced person like me as a researcher, I want to keep working towards the development of STAP cells to a level that could be helpful to someone," she said.
Explore further: New 3-D method improves the study of proteins