A genetic variant may explain why women develop multiple sclerosis (MS) nearly twice as often as men, says an international research team led by the Mayo Clinic."In practical terms, this is what our findings suggest: How much of the protein known as ‘interferon gamma’ you produce appears to be a new key variable in understanding who gets MS and who doesn’t,” study author and Mayo Clinic neurologist Dr. Brian Weinshenker said in a prepared statement."If you have a gene that produces high levels of interferon gamma, it may predispose you to developing MS. Under this scenario, men get MS less often because they have a lower frequency of a gene variant that is related to higher secretion of interferon gamma,” Weinshenker said.This finding may provide scientists with a new target for finding ways to stop MS or to improve treatment to minimize tissue and nerve damage caused by the disease."Our finding isn’t the whole genetic cause, but it’s a helpful step that could lead us to a more complete understanding of MS -- and ultimately, effective treatment. It’s also a very promising lead about gender differences that may pertain to susceptibility of other diseases, too, such as rheumatoid arthritis,” Weinshenker said.The study appears in the Jan. 27 online issue of Genes and Immunity.