What did a study of CFS patients' blood yield? A culprit, some researchers… (David Silverman / Getty…)
It's been a year since the journal Science published a paper linking a retrovirus called XMRV to chronic fatigue syndrome -- an illness nobody has been able to explain or treat very effectively, to the enormous frustration of people diagnosed with it.
The paper was met with expressions of hope and joy from many in the chronic fatigue syndrome community, who saw it as potentially leading to diagnostic tests, treatments and even, maybe, a vaccine and a cure.
But studies, even those published in prestigious journals such as Science, turn out to be wrong all the time, and their results need to be replicated before anybody can be relatively sure the findings were correct.
To that end, other research teams have attempted to find evidence of XMRV in chronic fatigue syndrome patients. Five different teams, including one led by the U.S. Centers for Disease Control and Prevention and another from the National Institutes of Health and the U.S. Food and Drug Administration, have published papers failing to find such evidence.
One of the teams, from the NIH and FDA, found evidence of a different retrovirus, one also associated with mice, in the patients, but nobody knows what that could mean.* [Updated Sept 30, 12:35 p.m.: In an earlier version of this article, the reference to the "different retrovirus" omitted the word "also," implying that XMRV is not associated with mice; it is.] It does not confirm the original paper.
So what is going on?
One esteemed retrovirologist, Dr. Robin Weiss of University College London, has just published his thoughts on the situation. They are worth a look.
Weiss' main point is that the history of retrovirology is littered with the debris of papers finding a link between a virus and a disease that later turned out to be false results caused by contamination. "There has been a long succession of ‘rumor' viruses posing as tumor viruses and promulgated as the cause of chronic human diseases," Weiss wrote.
Researchers at the Whittemore Peterson Institute for Neuro-Immune Disease, which led the team that published the original paper, have repeatedly denied they could have a contamination problem.
Weiss knows something about the issue. In 1997, his own team reported finding a retrovirus genome in patients with rheumatoid arthritis. Two teams -- one in Sweden, one in the U.S. -- "confirmed" his results. It seemed to be a breakthrough in rheumatoid arthritis.
But four years after Weiss reported his findings, he discovered he was actually detecting contamination from a newly discovered rabbit retrovirus.
"I raise an eyebrow when investigators declare that contamination is ‘out of the question'; once bitten, twice shy," Weiss said.
"My own skepticism," he wrote, "derives from a strong feeling of déjà vu."
Read "Push and pull over chronic fatigue syndrome."
-- Trine Tsouderos / Chicago Tribune