Journal Science retracts mouse virus link to fatigue

The 2009 study led by Dr Judy Mikovits, the director of the Whitmore Peterson Institute, found that the retrovirus XMRV was frequently present in the blood of chronic fatigue sufferers, without establishing a causal link.

But on Thursday Science said it had "lost confidence in the report and the validity of its conclusions" after multiple laboratories, including those of the original authors, failed to detect the virus in chronic fatigue patients.

It added that "there is evidence of poor quality control in a number of specific experiments in the (original) report" and important information omitted from the legend of one of the figures that appeared in it.

The journal said most of the authors had agreed in principle to retract the report but were unable to agree on the precise wording.

"It is Science's opinion that a retraction signed by all the authors is unlikely to be forthcoming. We are therefore editorially retracting the report.

"We regret the time and resources devoted to unsuccessful attempts to replicate these results," it added.

The study had been hailed as a breakthrough for the estimated one to four million Americans who suffer from the elusive but debilitating illness, and led to many being treated with antiretroviral drugs used against HIV/AIDS.

But earlier this year a separate group of researchers published an article in Science saying that the 2009 study was wrong and that its findings were likely based on contaminated lab samples.

Chronic fatigue syndrome is a mysterious disease that can last for years and cause memory loss, muscle pain, extreme tiredness and possibly insomnia.

The XMRV (xenotropic murine leukemia virus) causes cancer and other diseases in mice but not in humans.

It was detected in humans for the first time in samples of prostate cancer tumors in 2006 and is believed to be present in six to 27 percent of men afflicted with this form of cancer.

(c) 2011 AFP