The genetic background of ALS is multifaceted, involving both familial and sporadic forms of the disease. While the majority of ALS cases are sporadic, meaning they occur without a clear family history, approximately 5-10% of cases are familial and have a known genetic component. Familial ALS (fALS) accounts for a small percentage of ALS cases and is characterized by a clear family history of the disease. In these cases, ALS is inherited in an autosomal dominant manner, meaning that a mutation in a single copy of a specific gene is sufficient to cause the disease. Several genes have been implicated in familial ALS, including: