Fly study retracted

Researchers have retracted a study that pinpointed a specific gene in Drosophila required to maintain healthy cell activity, published two years ago in Current Biology. In a linkurl:retraction notice;http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VRT-4XF85VF-P&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=37ff9ee170319a71ae14c5c0a2a41692 published in the journal earlier this month (October 13), they attributed

Victoria Stern
Oct 19, 2009
Researchers have retracted a study that pinpointed a specific gene in Drosophila required to maintain healthy cell activity, published two years ago in Current Biology. In a linkurl:retraction notice;http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VRT-4XF85VF-P&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=37ff9ee170319a71ae14c5c0a2a41692 published in the journal earlier this month (October 13), they attributed the retraction to mistakes with the genetic model used to isolate gene activity as well as errors in the subsequent genetic crosses used to study the flies.
Drosophila
Image: Wikipedia
"Their original report ran counter to the thinking in the field, so I'm quite relieved to know that their result was dependent on another gene, or something else that we don't understand," wrote Lynne Cassimeris, a biologist from Leigh University in Pennsylvania who cited the paper in a linkurl:2009 study,;http://www.molbiolcell.org/cgi/content/abstract/20/15/3451 in an email to The Scientist. linkurl:Georgina Fletcher,;http://www.cancerresearchuk.org/ a postdoctoral fellow at Cancer Research UK in London, and linkurl:Pernille Rørth,;http://www.imcb.a-star.edu.sg/php/pr.php deputy director of the Institute of Molecular and Cell Biology in Singapore, reported in the 2007 paper that when a protein called stathmin stopped working, cells could no longer function normally. The study has been cited four times, according to ISI. Previous studies have shown that stathmin is present at high levels in many human cancers, but whether the protein somehow causes cancer remains to be determined. Rørth explained in an email that Fletcher, then a postdoc in her lab, cloned a gene in the wrong orientation but did not realize it, and performed the genetic fly crosses incorrectly. Additionally, it just so happened that there was a gene right next to the gene of interest that revealed the phenotype they were expecting. "So the effects we saw were all real, just due to the gene next to the one we were studying," she wrote. The authors said in the retraction notice that later analysis suggested their model had not isolated stathmin function in Drosophila, and thus their results could be attributed to the activity of two genes. They verified the error by redoing the experiment but silencing stathmin activity, and found that the effects of stathmin were not significant. "I'm afraid the mistakes were quite specific to the project, and not any that could be drawn on by a wider range of scientists," Fletcher wrote in an email to The Scientist. "We were just unlucky, with certain unusual circumstances coming together." Cassimeris, who studies stathmin function in cells but is not a Drosophila geneticist, wrote that it seems reasonable that the original phenotype they reported actually depended on the second gene, or on a combination of stathmin and the protein expressed by the second gene. "Assigning a phenotype to a wrong gene (for example an adjacent gene) happens sometimes - both with flies and other genetic organisms - as the tools we use for gene disruption are not perfect," Rørth wrote in the email. Often, she added, those mistakes lie dormant in the literature. "In this case, it was quite clear to us that the result was wrong, so correcting it was clearly the right thing to do." Editor's note (October 20): This story has been updated from a previous version to include comments from Pernille Rørth.
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[15th March 2004]*linkurl:Drosophila and e. coli share a strategy for signal release;http://www.the-scientist.com/article/display/13374/
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