After losing key data under strange circumstances, a team of University of Utah molecular biologists this month retracted two published studies about regulation of iron in the blood.
The retracted articles, which also contained errors in explanatory figures or graphics, were published last year in Cell Metabolism, part of the Cell Press family of journals published by Elsevier. The papers represent a small slice of the prodigious output of the lab of veteran pathology professor Jerry Kaplan, the U.'s assistant vice president for health science research.
The errors and lost data do not undermine the studies' conclusions, according to a post by the Kaplan group on the journal's website. Kaplan's lab sought the retractions "because a number of errors have been detected in the assembly of the figures, and some of the original data were inappropriately removed from the laboratory," the lab group wrote. "We stand by the validity of our studies; the data are reproducible, and the conclusions were not affected by the errors.
Kaplan said Tuesday that the data in question were in notebooks thrown out by a lab technician, who has been dismissed from U. and was not a named author. He declined to elaborate.
The retractions raise questions about one of the U.'s most productive health science labs, which handles millions of dollars in federal grants and publishes regularly in top-shelf science journals.
The research in question is supported almost entirely by taxpayers, and the U. has issued press releases publicizing other research findings from the Kaplan lab connected to the compromised studies. But U. administrators declined Tuesday to provide details or an explanation of what went wrong. Nor will they confirm whether they are investigating.
"We appreciate your interest in this matter but the University does not comment on the existence or status of investigations," spokesman Chris Nelson wrote in an e-mail.
The retraction announcement no longer appears on Cell Metabolism's site, but it remains quoted on the blog Retraction Watch. Meanwhile, one of retracted studies is available for download from the ScienceDirect website for a fee, with no indication it has been retracted.
A phone message left with a Cell Press spokeswoman was not returned.
Retractions are a growing problem in scientific literature, according to a recent article published in Nature. A retraction is the most extreme action a journal can take against a study it publishes, an acknowledgement that is it so flawed it must be pulled from publication.
Between 2001 and 2011, there has been more than a 10-fold increase in the number of retracted studies each year, while the number of studies published has risen only 44 percent, reported Nature, one of the world's most prestigious science journals. The problem is exacerbated when journals fail to publicize retractions or issue opaque explanations because other scientists are likely to continue citing a flawed study long after it has been discredited.
Research led by John Budd, an information science professor at the University of Missouri, has documented hundreds of instances where retracted biomedical studies were cited by other scholars after they were retracted. Only rarely is the retraction acknowledged in the citation.
According to Retraction Watch, one of the retracted U. studies has already been cited three times.
Retractions are not the only headache for the Kaplan lab. It also has corrected a third paper published in 2009 in the Proceedings of the National Academy of Sciences (PNAS), fixing numerous errors in figures that supported the study's findings. Some of the group's subsequent research findings cite this study, which explores the role of the hormone hepsidin in iron regulation.
The lead author on all three tainted studies is Ivana De Domenico, an assistant professor of internal medicine.
A grant from the National Institute of Diabetes and Digestive and Kidney Diseases funds the research underlying the retracted studies. This grant, titled "Factors regulating the cellular uptake of iron," has supported the Kaplan lab's work since 1988, amounting to $350,000 in recent years, according to the National Institutes of Health. Two other NIH grants support the research underlying the corrected PNAS study.
Iron is an essential nutrient that can wreak havoc if it accumulates in the blood. Too little causes anemia, the condition where the oxygen-carrying ability of the blood is diminished. Kaplan's research seeks to understand how iron is passed in and out of cells in the hope of developing new ways to diagnose and manage diseases associated with the mis-regulation of iron.