Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a neurodegenerative disease that strikes nearly 5,000 people in the U.S. every year. About 10% of ALS cases are inherited or familial, often caused by an error in the C9orf72 gene. Compared to sporadic or non-familial ALS, C90rf72 patients are considered to have a