From The Guardian, 6 January 2010 (page 6). Story by Sarah Boseley.
Serious doubt has been cast on the theory that made headlines around the world last October that chronic fatigue syndrome, or ME, is caused by a new retrovirus.
Scientists at Imperial and King's universities in London have attempted to replicate work carried out in the US and published in the journal Science last autumn. But they found not one of the 186 patients they studied had a trace of the novel virus, called XMRV, in their blood samples.
The theory, which made headlines around the world last October, gave hope to many. About three in every 1,000 people, possibly more, suffer from chronic fatigue syndrome (CFS), formerly known as myalgic encephalomyelitis (ME), which is a condition described one of the authors of the paper, Dr Anthony Cleare, reader in psychiatric neuroendocrinology at King's, as serious and debilitating and extremely frustrating for sufferers who do not know its cause.
The study in Science, by Vincent Lombardi and colleagues at a small private pathology laboratory in Reno, Nevada, sent many patients hurrying to doctors for tests and antiretroviral drugs.
Lombardi and his team reported that they had found the virus XMRV in 67% of the CFS patients they tested. Later they said they had found it in 95% of patients. Lombardi has devised and sells a test for the virus in north America.
Scientists around the world embarked on their own tests, and Dr Cleare and his colleagues are the first to publish results. “If this research is replicated, it is potentially a huge breakthrough in understanding this condition,” he said.
King's College hospital runs a specialised CFS/ME clinic. The researchers selected blood samples from 186 patients who were, they said, typical of those who attend. They had suffered for years, were very disabled by the disease and more than 90% said their illness definitely or probably started after a viral infection.
They sent the samples to a team at Imperial's retrovirology labs. Professor Myra McClure, from the division of medicine at Imperial College London and one of the authors of the study published today by PloS One(Public Library of Science), said: “Our research was carried out under rigorous conditions. We used very sensitive testing methods to look for the virus. If it had been there, we would have found it.
“The lab in which we carried out the analysis had never housed any of the murine leukaemia viruses related to XMRV, and we took great care to ensure there was no contamination. We are confident our results show there is no link between XMRV and CFS, at least in the UK.” The authors say there is no evidence to justify testing people with CFS for the virus or putting them on drug treatment.