2002-09-02 10:01:02 -0400
By Linda Carroll
Certain genetic variations may make some people more prone to developing multiple sclerosis (MS), researchers have found.
According to European scientists, these genetic variations could make it difficult for the immune system to distinguish between the Epstein Barr virus (EBV) and myelin--the fatty material that insulates the nerves and allows them to transmit electrical signals, according to a report in the advance online publication of Nature Immunology.
When the immune system mistakes myelin for EBV, it attacks it. Electrical signals in the body then slow down or become garbled, which leads to the symptoms experienced by MS patients. But exactly what triggers this misguided immune system assault is unclear.
The study by Lars Fugger of the Aarhus University Hospital in Skejby Sygehus, Denmark, and colleagues found that a genetic variation in an MS patient made the patient's immune system more likely to confuse myelin for EBV.
The study gives more credence to the notion that the body might be mistaking proteins of the central nervous system for proteins in the virus, said Dr. Clyde Markowitz, co-director of the MS Center at the University of Pennsylvania in Philadelphia.
"The new study fulfills a lot of expectations," agreed Dr. James R. Miller, director of the MS Center at Columbia-Presbyterian Medical Center in New York. "For some time we've known there was some relation between viral and MS attacks. This doesn't mean the virus is the cause of MS, but it shows how viruses might trigger it."
Ultimately, Miller noted, researchers may find that more than one type of gene variation leads to susceptibility to MS.
SOURCE: Nature Immunology online 2002.
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