Scientists are honing in on the genetic roots of the most common form of Lou Gehrig's disease.
Researchers form Johns Hopkins say they have identified 34 genetic variations among patients with the disease.
That means there is a good chance at least some of these variations put people at risk for the uninherited form of the disease.
About 10,000 Americans die from Lou Gehrig's disease each year.
An estimated one in 2,000 people are at risk of developing the neurodegenerative disease.