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Scientist faces irreproducible results

January 27, 2006 By Ichiko Fuyuno This article courtesy of Nature News.

RNA researcher defends experiments others have found impossible to repeat.

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After the spectacular case of fraud involving stem-cell researcher Woo Suk Hwang, Asia has been hit by another, more low-key scandal.

The head of an investigating committee at the University of Tokyo announced on 27 January that at least one of the experiments performed by a Japanese RNA researcher, whose credibility stands in doubt, has failed a first test to reproduce the results.

In April last year, the RNA Society of Japan asked the University of Tokyo to examine 12 papers written by Kazunari Taira and his team between 1998 and 2004. This was in response to a number of complaints from international researchers that they could not reproduce the experimental results.

The main focus of Taira's work is RNA interference technology, in which small pieces of RNA, either naturally present or introduced into cells, regulate expression of genes. The work, which has been questioned for some time, addresses smaller aspects of RNA research and is not considered central to the field.

The university has set up an investigating committee, which includes outside experts. They first asked Taira to submit raw data, but he could not do so. His assistant and first author of most of the papers, Hiroaki Kawasaki, admitted that he had not kept his notebooks. It also seems that some data stored in a computer had been deleted (see ' Lack of lab notes casts doubt on RNA researcher's results').

I didn't do anything wrong
Hiroaki Kawasaki
So the committee asked Taira and his team to reproduce experiments described in 4 of the 12 papers, chosen because they looked relatively easy to perform. These included two Nature papers1,2, the first of which had already been retracted, and the second corrected.

Mixed results

Now the results are in from the first of these tests. On 13 January, Kawasaki reported that he could repeat the results outlined in their 2003 paper published in Nucleic Acids Research3. But an independent company also attempting it could not.

The investigating committee has decided not to accept Kawasaki's new results, in part, they say, because the team did not use the same materials as outlined in the original paper. They also note that while Kawasaki's notebooks indicate that he used Rosetta-gami bacteria in the new experiment, it seems that he used Rosetta-gami DC3 instead; a potentially worrying discrepency.

Taira says that Kawasaki is willing to do the test again in front of witnesses.

Officials from the university did not discuss whether scientific fraud or fabrication were involved. Kimihiko Hirao, head of the School of Engineering and spokesperson for the committee, said at a press conference on 27 January "there are many things that look doubtful".

"I didn't do anything wrong," Kawasaki says, adding that he didn't know the importance of keeping notebooks until recently.

Last week, various news outlets reported that Taira said that an assistant may have fabricated some data.

Try, try again

Taira's team is working on re-doing a second of the four papers. They have not yet tackled the third and fourth.

The investigating committee originally said it would deliver a final verdict in March. Meanwhile the university has set up another committee to specifically investigate who in Taira's team, which includes about 30 people, was responsible for what aspects of the various papers.

Taira says he does not intend to resign from his post but will follow any advice from the investigation. He adds that he has no plan to retract the 2003 paper. There's no complete evidence of wrongdoing, Taira says. "The biggest problem is the absence of notebooks."

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  1. Kawasaki H.& Taira K. . Nature, 423 . 838 - 842 (2003).
  2. Kawasaki H.& Taira K. . Nature, 431 . 211 - 217 (2004).
  3. Kawasaki H., Suyama E., Iyo M.& Taira K. . Nucleic Acids Res., 31. 981 - 987 (2003).


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