Study Links Virus to Chronic Fatigue Syndrome

Posted: October 8, 2009

WASHINGTON—A virus recently linked to prostate cancer is a new suspect in chronic fatigue syndrome. U.S.scientists tested blood from 101 patients and found two-thirds carried it.

That does not mean the virus causes chronic fatigue, stressed the research published Thursday in the journal Science.

The team of scientists from the National Cancer Institute and Nevada's Whittemore Peterson Institute said it was possible the virus, named XMRV, was just "a passenger virus" that catches a ride in patients whose immune systems are weakened by chronic fatigue.

Moreover, the researchers found nearly 4 percent of healthy people carried the virus, too. That raises bigger questions about just what role this recently discovered virus — a relative of viruses that cause cancer in mice — may be playing in overall health.

"This suggests that several million Americans may be infected with a retrovirus of as-yet-unknown pathogenic potential," the researchers concluded.

A retrovirus is a kind of virus that permanently embeds in the body.

Various viruses have been linked to chronic fatigue over the years, only to fall by the wayside as potential culprits in the mysterious illness thought to afflict millions. It is characterized by at least six months of severe fatigue, impaired memory and other symptoms, but there's no test for it — doctors rule out other possible causes — and no specific treatment.

The XMRV virus is related to mouse leukemia viruses. No one knows how it arose or how people become infected. But another research team recently found the virus lurking in about a quarter of 200 prostate tumors — and in about 6 percent of noncancerous prostate samples they used for comparison.

"There is still much that we do not understand," including whether people with either disease just are more prone to infection, cautioned Tufts University microbiologist John Coffin in an accompanying editorial. Still, "further study may reveal XMRV as a cause of more than one well-known 'old' disease."

In Wikipedia you can read the following;

From Wikipedia, the free encyclopedia

Xenotropic murine leukemia virus-related virus (XMRV), sometimes shortened to Xenotropic MuLV-related virus, is a newly identified and provisionally named gammaretroviruswhich may be involved in the pathology of familial prostate cancer and chronic fatigue syndrome. Its name refers to its similarity to xenotropic murine leukemia viruses, although it does show some substantial differences. It is thought to be linked to both prostate cancer and chronic fatigue syndrome by ribonuclease L (RNase L), part of the cell’s natural defense against viruses. When activated, RNase L destroys RNA in an effort to halt viral gene expression.

Previous research has shown that R462Q mutation that results in a decreased level of RNase L function, was associated with more susceptible XMRV infection in men; however, a later study has found that XMRV infection typically occurred independent of the RNase L gene variation.^[1]

The virus was discovered in cancerous prostate tissues using a microarray containing samples of genetic material from over 1,000 viruses. The screen revealed the presence of a gammaretrovirus in a substantial number of the homozygous R462Q cells, but very few of the heterozygous or wild type cells. An expanded screen showed the virus present in 40% of men homozygous for R462Q and only 1.5% of those not, and also demonstrated that each case showed the same virus.^[2] In another study, the viral genome was reconstructed from prostatemRNA and used to infect prostate tissues in vitro. The researchers were able to show that RNase L deficient lines were more susceptible to infection.^[3] These data do not necessarily show that XMRV causes prostate cancer, but they do show that RNase L deficiency makes prostate tissue more susceptible to the virus. This in turn suggests the possibility of a link between the virus and the disease.

XMRV has been even more strongly implicated in chronic fatigue syndrome: according to a study published in Science people with CFS are 54 times more likely to be infected with XMRV than the average individual.^[4][5]

It has been suggested that XMRV could be sexually transmitted.^[6][7][8]

 

This is an interesting development, especially for me personally. I have battled CFS/ ME for 5 years and have been unable to work, my daily functioning is down by 80%. Before I got ill I worked fulltime, I raced on my bike for hours/ week, and I walked 2 hours/ day. Any news is good news!