Immune system defect may cause MEResearchers in Norway believe Chronic Fatigue Syndrome (CFS), also known as ME, may be caused by a wayward immune system attacking the body.
The illness, the cause of which is uncertain and has no known cure, has attracted significant controversy.
A small study, reported in PLoS One, showed a cancer drug, which inhibited the immune system, relieved symptoms in some patients.
The ME Association said the findings were "very encouraging news".
Doctors in Norway stumbled across their first clue in 2004 when treating a patient with both Hodgkin's lymphoma, a cancer of the white blood cells, and CFS.
When she received cancer treatment, her fatigue symptoms improved for five months.
http://www.bbc.co.uk/news/health-15401746