Counter to research published in 2009, chronic fatigue syndrome might not be linked to infection with xenotropic murine leukemia virus (XMRV), according to two studies published by the journal Science and reported by The New York Times. One study found no sign of XMRV in the bloodstream of 43 patients who’d previously tested positive for the retrovirus. In the second study, scientists found evidence that XMRV may be a recombination of two mouse viruses formed accidentally in the lab. Previously, some people with chronic fatigue syndrome had taken HIV-fighting antiretrovirals because they had been shown to thwart XMRV replication.

To read the Times article, click here.