Among them, mutations in the C9orf72 gene, which are particularly expressed in B cells and characterized by an expansion of the GGGGCC sequence within an intronic region [10], represent the most frequent cause of inherited ALS, and they indirectly reveal the close relationship between the disease and the active participation of the clonotypic immune system. This evidence concerns the gene C9orf72 and amyotrophic lateral sclerosis.