MS is a potentially debilitating disease in which your body’s immune system eats away at the protective sheath that covers your nerves. This interferes with the communication between your brain and the rest of your body. Ultimately, resulting in deterioration of the nerves themselves, a process that’s not reversible.

For decades, MS researchers have been forced to make their best guess as to what causes this disease, which affects 300,000 Americans, mostly women, between their 20s and 40s.  

Researchers report that they have identified two new genes that may contribute to the immune disorder multiple sclerosis (MS). The hope is that the discovery will someday lead to the development of more efficient and much-needed MS drugs, as today’s therapies carry serious side effects and address the disease’s symptoms, but not its cause.

The new genes are the first to be linked directly to MS since the 1970s, when researchers initially identified a cluster of DNA on chromosome 6 associated with immune system function. Doctors believe MS is an autoimmune disease, in which the body mistakenly attacks its own healthy cells. But they have never been able to figure out why the body turns on itself, and they hope these new genes may offer a clue. “This is by no means the final, whole answer, but we’ve gotten an incredible glimpse into the cause of the disease,” says Dr. David Hafler, professor of neurology at Harvard Medical School.

As exciting as the discovery is, it’s a small part of the story: the new genes account for less than 1% of the risk of developing MS.  

For more on this article and findings http://www.time.com/time/health/article