Posted by Phillipa on August 24, 2010, at 18:45:53 [reposted on August 27, 2010, at 22:52:09 | original URL]
Now they are saying Chronic Fatigue syndrome may have a mutation in peoples blood both healthy and sick and they are looking as to how it could affect the nations blood supply. Phillipa
Medscape Medical News
More Evidence Links Murine Virus to Chronic Fatigue Syndrome
Fran Lowry
August 24, 2010 Scientists from the U.S. Food and Drug Administration's (FDA's) Center for Biologics Evaluation and Research and the National Institutes of Health (NIH) have found murine leukemia virus (MLV)related gene sequences in patients with chronic fatigue syndrome (CFS) and in some healthy blood donors.The finding, which was published online August 23 in Proceedings of the National Academy of Sciences United States of America adds to the evidence that a virus may play a role in some, if not all, cases of CFS.
It also lends support to an earlier study by Lombardi and colleagues (Science. 2009;326:585-589) that found xenotropic MLV-related virus (XMRV) a genetic variant of MLV-like viruses in the peripheral blood mononuclear cells of patients with confirmed CFS.
The researchers, led by Shyh-Ching Lo, MD, PhD, of the FDA in Bethesda, Maryland, tested blood samples from well-pedigreed CFS patients using polymerase chain reaction. They found evidence of MLV in 32 of 37 patients with CFS (86.5%) compared with only 3 of 44 healthy volunteer blood donors (6.8%).
"Dramatic Association"
"There is a dramatic association with chronic fatigue syndrome, but that's all it is," senior study author Harvey Alter, MD, of the NIH, told reporters in a telebriefing. "It's an association, and we have to emphasize, as we did in the paper, that we have not found causality for this agent. There are many, many more pieces that we have to fit into the puzzle."
The findings from the 2 studies are in stark contrast to those from Europe and the United States, including a study from the Centers for Disease Control and Prevention (CDC), which failed to find any evidence of XMRV or MLV in the blood of CFS patients.
There are many possible explanations for this lack of concordance, Dr. Alter said. "Probably the most prominent is the fact that chronic fatigue syndrome is a symptom complex, and there is no specific tissue you can biopsy or no specific test in CSF patients. It's probably a spectrum of patients, and some may be associated with XMRV or MLV and others due to other agents or no viruses at all. That has to be sorted out."
Steve Monroe, PhD, from the CDC, Atlanta, Georgia, said that the conflicting results from different laboratories suggest that there is much about this virus that is unknown. "There are lots of things about the biology of the virus, how it interacts with humans, where it replicates, what kind of disease it causes, if any, what are the best samples to use for diagnosis, how the samples should be collected and processed, and what tests should be used. So there are a lot of things that remain to be learned about the virus."
Hira Nakhasi, PhD, of the FDA's Office of Blood Research and Review, admitted that the conflicting results were of concern and outlined steps that were being taken under the auspices of the National Heart, Lung, and Blood Institute to shed more light on the issue.
"There is an XMRV scientific research working group which is developing tools to allow labs to standardize methodologies among themselves and to look at the clinical samples and develop panels which will be used to standardize the methodology," he told Medscape Medical News. "This is a concern, and therefore these studies will be followed up."
The finding that MLV-related virus gene sequences are present in nearly 7% of health volunteer blood donors in the current study, and also in a small percent 3.7% of healthy controls in the Lombardi study, raises additional issues for the safety of the nation's blood supply, Dr. Lo stated.
"The possibility that these agents might be blood transmitted and pathogenic in blood recipients warrants extensive research investigations of appropriately linked donor-recipient cohorts."
poster:Phillipa
thread:960254
URL: http://www.dr-bob.org/babble/health/20100104/msgs/960254.html