Amid accusations of scientific misconduct, a prominent South Korean scientist said Friday that he has requested the withdrawal of a landmark scientific paper on stem cells created through human cloning. However, Woo Suk Hwang insisted that the work would be confirmed as sound when fresh tests are conducted in the next couple of weeks.
The paper, which was prepared by an international research team led by Hwang and published by the journal Science in May, purported to show how individual stem cell colonies were created for 11 patients through cloning. At the time, scientists said the breakthrough could eventually lead to finding cures for illnesses like diabetes and Parkinson's disease.
But during meetings with journalists in Seoul on Friday, Hwang said he asked the journal to withdraw the report due to problems with the accompanying photos, apologizing for "fatal errors and loopholes in reporting the scientific accomplishment."
Previously, Hwang's team told Science only that some duplicate photos of the same stem cell colonies had accidentally been printed, and last week the journal's editors said those mistakes did not affect the findings. Since then, increased scrutiny by Korean journalists has led to more serious concerns about the fabrication of data.
On Friday, Science editor-in-chief Donald Kennedy said Hwang and the senior author of the paper, the University of Pittsburgh's Gerald Schatten, formally requested a retraction during phone calls to the editors. Kennedy quoted them as saying the procedures used to confirm the creation of separate lines of cloned stem cells "could not be trusted."
Hwang promised Science that he would get the consent of the paper's 24 other authors and work out the precise language for the retraction, including an explanation of what went wrong, Kennedy said. The time frame for that process should be "measured in days and weeks and not months," he said.
If the researchers do not follow through on Hwang's pledge in a reasonable time, Science may issue its own editorial retraction. Such a retraction represents a serious blow for all the researchers involved — and particularly for Hwang, who was hailed as the world's foremost expert on cloning until only a few weeks ago.
Hwang insisted that although the Science paper was fatally flawed, the findings behind it were sound.
"Our research team made patient-specific embryonic stem cells, and we have the source technology to produce them," Hwang told a news conference.
Under fire for weeks
Hwang's work has been under fire for weeks, but the latest round of questions came Thursday when a former collaborator accused him of pressuring a lab worker to forge evidence. Roh Sung-il, chairman of the board at Mizmedi Hospital and a co-author of the article, maintained Friday that Hwang still was not telling the truth.
"He's avoiding taking the responsibility that he should take," Roh said, questioning the validity of Hwang's claims that he created 11 stem cell colonies.
"Nine stem cells appear to be fake, and two others are not confirmed yet," Roh, who provided Hwang with human egg cells for the research, told The Associated Press.
The researcher from Roh's hospital who reportedly was ordered to fabricate results defended Hwang on Friday. In an interview with KBS television in the United States, where he is assigned to the University of Pittsburgh, Kim Sun-jong said he had personally seen eight stem cell lines and another three being nurtured.
"The stem cells were cultivated through normal procedures, and eight members of Hwang's research team verified them every morning," Kim told KBS.
Hwang insisted earlier that the 11 stem cell colonies were created "without 1 percent of doubt." He said some of the cells he created died after being contaminated, but that cells were now being unfrozen that would prove the validity of his work within 10 days.
But Roh said Hwang's attempts to prove the authenticity of the experiments would not work. Roh said Hwang told him Thursday there were no embryonic stem cells remaining from the experiments because all the colonies died in the lab.
"What can I say if Hwang changes the remarks he made with his own mouth yesterday?" Roh told AP.
Government waits to take action
After an emergency meeting chaired by Prime Minister Lee Hae-chan, the South Korean government said it would wait to take further action until after an internal probe by Seoul National University, where Hwang works. The university announced Friday it had appointed a nine-member investigation panel — seven from within the university and two from other South Korean institutions — to look into the allegations.
Hwang is considered a national hero in South Korea and is strongly supported by the government, which has given him nearly $25 million for his research. The allegations have shocked the country, even sending shares on the South Korean stock market plummeting downward Friday morning.
Hwang's work has recently come under a cloud of suspicion. Last month, he publicly apologized after admitting that, despite earlier denials, he used eggs from two female scientists in his lab — a violation of international ethics guidelines.
Hwang has also stepped down as head of the World Stem Cell Hub, an international project launched in October aimed at finding treatments for incurable diseases.
Other scientists react
Douglas Melton, co-director of the Harvard Stem Cell Institute, said Thursday through a spokesman he was "truly saddened" to hear the allegations against Hwang. But, he said, "stem cell science holds too much promise to allow this incident to detract from the careful, closely supervised work being done in the U.S."
Other scientists stressed Thursday that the fraud accusations against Hwang have not been proven.
"We have to give him the benefit of the doubt right now," said cloning researcher Peter Mombaerts of Rockefeller University in New York.
He said Hwang and a colleague appeared confident and believable when top cloning researchers questioned them about the work at a scientific meeting Nov. 9 before the accusations arose.
"They withstood the test," Mombaerts said.
But if substantial fraud is proved, scientists said, it would cast doubt on Hwang's other work, including his report last year of the first cloned human embryos from which stem cells were extracted, and his announcement in August of the first cloning of a dog.
This report includes information from The Associated Press and MSNBC.com.