BOSTON, July 7 (UPI) — A recent study that found genes could predict how long a person could live sounded too good to be true, and several researchers say it was.
Since the research by Boston University was published in Science, geneticists began digging into the research and came up with something that may have altered the data, Newsweek reported Wednesday.
The culprit? A DNA chip, called a 610-Quad, used to identify and sequence DNA and which apparently tends to get some small — but critical — details wrong, the researchers said. The flaw could cloud the study’s strongest results, suggesting they stem from a lab mishap instead of a true link to long life.
The study identified a small set of DNA variations called genetic markers that can predict “exceptional longevity” with 77 percent accuracy, it was reported last week. There’s no single “longevity gene,” the study said, but a cumulative effect of almost 150 markers, and different people show different markers.
All DNA chips used in the Boston University study came from the same manufacturer, but they weren’t identical, Newsweek reported. The researchers said they used two different chips to look at their centenarians, analyzing most people with a 370 chip that examines 370,000 genetic variants and a smaller fraction of people with the 610-Quad that examines 610,000 variants.
While the team said it conducted extensive quality-control procedures and cleaning of the data, it apparently didn’t get a third-party analysis of their centenarians’ and controls’ DNA using a single DNA chip for everyone.
There’s “nothing in the world simpler to do,” said Duke University geneticist David Goldstein, who first raised the issue. “We would do this for any discovery we had in this kind of a situation, but when the results themselves are a bit improbable, as the results are here with the exceptional genetic control, then there is all the more necessity for that quality-control step.”
Soon after the Newsweek article was published, the study’s authors said in a statement they have been made aware of a technical error in the lab and criteria used to determine the significance of the individual variants.
The authors said they were “closely re-examining” the analysis because of the attention drawn to the lab issue.
Concerning the criteria issue raised, the authors said they used standard criteria for the analysis, “and we are confident that the appropriate threshold was used.”
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