Navigation Links
Studies Refute Virus' Link to Chronic Fatigue Syndrome

By Amanda Gardner
HealthDay Reporter

TUESDAY, May 31 (HealthDay News) -- A virus identified two years ago as a possible cause of chronic fatigue syndrome now turns out not to be the culprit, new research says.

Experts say it's a major setback in the effort to understand and treat this mysterious and debilitating disease.

The authors of a new study published May 31 in Science find that the so-called XMRV viral pathogen spotted in human samples in the prior study (published by the same journal in 2009) likely got there as a result of "genetic recombination." That can occur in the laboratory when DNA from different viruses mix.

In this case, two mouse viruses combined and the product of that union then contaminated the human specimens via "reagent" compounds used in the lab, the new research shows.

This probable contamination of the samples with XMRV in the lab "means that this virus has no proven association" with chronic fatigue syndrome, said Stuart LeGrice, head of the lab that oversees all XMRV research at the U.S. National Cancer Institute, which conducted the new study.

"I believe the evidence is incontrovertible," he added. "It doesn't rule out the possibility that there's another retrovirus [involved] but, as of right now, we're close to 100 percent certain that this eliminates the virus as a causative agent of either condition."

The study was accompanied by a rare "Expression of Concern" from the editors of Science. While they did not call for an outright retraction of the original paper, the editors pointedly questioned the study's validity.

According to the Wall Street Journal, the editors of Science have asked the authors of the 2009 paper to voluntarily retract their paper. The authors have responded that any retraction would be "premature," the newspaper reported.

This sequence of events began two years ago, with the publication of a finding that about two-thirds of patients with chronic fatigue syndrome sampled were infected with XMRV, which stands for xenotropic murine leukemia virus-related virus. These viruses can cause cancer and other problems in mice and they can infect human cells in the laboratory.

At the time, the finding raised hopes that there might finally be a concrete cause for chronic fatigue syndrome and perhaps, down the line, treatments for the disease.

The illness affects an estimated 1 percent of people worldwide and, as its name implies, involves crippling fatigue as well as aching joints, headaches and various other symptoms.

Unfortunately, subsequent studies by other researchers failed to replicate the findings.

The authors of the new study looked at blood samples from 61 people with chronic fatigue syndrome. The samples came from the same source that had supplied samples for the 2009 study. Forty-three of the samples had earlier been diagnosed as positive for XMRV.

However, this time around the researchers avoided using any lab products derived from mice. This time, they found no evidence at all of XMRV in any of the 61 samples.

"We're learning a very important lesson that even some commonly used reagents [compounds used in scientific experiments] contain trace amounts of contaminating mouse DNA," said LeGrice, who is head of the Center of Excellence in HIV AIDS/Cancer Virology at the National Cancer Institute. "But, using diagnostic technologies that are ultra-sensitive, we can easily pick out the contaminating material. The contaminants somehow got into the samples [but] we have to be absolutely clear that this virus was never in humans."

A second study in the same issue of the journal had similar problems trying to replicate earlier research linking XMRV with prostate cancer tumors, for much the same reasons. That study was led by Jay Levy of the University of California, San Francisco.

A statement from the Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS) Association of America said that "these studies add to the mounting number of publications that challenge the reliability of the initial report."

The U.S. National Institutes of Health is sponsoring additional studies on XMRV and chronic fatigue syndrome.

"We will support the outcome of those studies, whichever way they lead," the CFIDS statement said.

More information

There's more on chronic fatigue syndrome at the U.S. Centers for Disease Control and Prevention.

SOURCES: Stuart LeGrice, Ph.D., head, Center of Excellence in HIV AIDS/Cancer Virology, U.S. National Cancer Institute; statement, CFIDS Association of America; May 31, 2011, Science

Copyright©2010 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Cigarette Packaging Still Too Alluring, Studies Find
2. Studies show Vectra(TM) DA can track early response to rheumatoid arthritis therapy
3. Crime Victims Institute studies adolescent sex and laws
4. ASCO releases studies from upcoming annual meeting
5. 2 new studies describe likely beneficiaries of health care reform in California
6. Mayo Clinic studies how much practice makes perfect when performing colonoscopies
7. Animal studies reveal new route to treating heart disease
8. New studies show negative effects from revised mammography recommendation for women, ages 40-49
9. Mammograms Can Save Lives of Women in Their 40s: Studies
10. IADR/AADR Journal of Dental Research releases studies on oral health inequalities in older people
11. Worm studies shed light on human cancers
Post Your Comments:
Related Image:
Studies Refute Virus' Link to Chronic Fatigue Syndrome
(Date:6/27/2016)... Lafayette, California (PRWEB) , ... ... ... a pioneer in the patient payment industry today announced its strategic partnership ... and health system workflows. , The two companies’ proven, proprietary technology combine ...
(Date:6/26/2016)... , ... June 26, 2016 , ... Pixel Film Studios ... X. , "Film editors can give their videos a whole new perspective by using ... - CEO of Pixel Film Studios. , ProSlice Levels contains over 30 Different ...
(Date:6/25/2016)... ... ... Austin residents seeking Mohs surgery services, can now turn to Dr. Jessica Scruggs ... for medical and surgical dermatology. , Dr. Dorsey brings specialization to include Mohs surgery, ... Micrographic Surgery completed by Dr. Dorsey was under the direction of Glenn Goldstein, MD, ...
(Date:6/25/2016)... ... June 25, 2016 , ... Dr. ... from injury. Recently, he has implemented orthobiologic procedures as a method for treating ... one of the first doctors to perform the treatment. Orthobiologics are substances that ...
(Date:6/24/2016)... ... 24, 2016 , ... June 19, 2016 is World Sickle Cell Observance Day. ... the benefits of holistic treatments, Serenity Recovery Center of Marne, Michigan, has ... , Sickle Cell Disease (SCD) is a disorder of the red blood cells, which ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Roche (SIX: RO, ROG; ... for its Elecsys BRAHMS PCT (procalcitonin) assay as a ... septic shock. With this clearance, Roche is the first ... integrated solution for sepsis risk assessment and management. ... infection and PCT levels in blood can aid clinicians ...
(Date:6/23/2016)... Pa. , June 23, 2016 Bracket ... will launch its next generation clinical outcomes platform, Bracket eCOA ... Meeting held on June 26 – 30, 2016 in ... the first electronic Clinical Outcome Assessment product of its kind ... Booth #715. Bracket eCOA 6.0 is a flexible ...
(Date:6/23/2016)... -- Revolutionary technology includes multi-speaker listening to ... leaders in advanced audiology and hearing aid technology, has ... the world,s first internet connected hearing aid that opens ...      (Photo: ) , ... firsts,: , TwinLink™ - the first dual ...
Breaking Medicine Technology: