Xenotropic murine leukemia virusrelated virus (XMRV) has been the subject of many studies since its discovery in 2006, but conflicting reports have created an unclear picture of XMRV's role in human disease. In three recent studies published in the November 15 issue of The Journal of Infectious Diseases, now available online, the evidence supports a possible link between XMRV and prostate cancer but not other links involving chronic fatigue syndrome, HIV infection, or hepatitis C virus (HCV) infection. (Please see below for links to these articles online.)
In one of the studies, led by Athe Tsibris, MD, investigators from Boston determined XMRV prevalence in a variety of North American clinic populations. The study included healthy subjects, participants with CFS, and participants with chronic immune activation or suppression. Study samples were obtained from adult patients presenting to outpatient clinics or from pre-existing samples at Brigham and Women's Hospital, Massachusetts General Hospital, and Dana-Farber Cancer Institute. Researchers did not detect XMRV in any of the 293 patients tested, and the investigators did not find an association between XMRV and patients with CFS, chronic immune suppression, or medical conditions associated with chronic immune activation.
Researchers were surprised that they did not detect XMRV in any of the study participants, despite the high prevalence previously reported. A previous study in the United States found evidence of XMRV DNA in 67 percent of subjects with chronic fatigue syndrome (CFS), compared to 3.7 percent of healthy controls. Subsequent studies in Europe, however, were unable to demonstrate the presence of XMRV in CFS subjects or healthy controls.
"The findings suggest that in the population we tested, XMRV is not associated with chronic fatigue syndrome and suggests that differences in PCR technique from study to study do not explain the disparate results seen in XMRV s
|Contact: John Heys|
Infectious Diseases Society of America