Mutations in several genes are widely accepted as relevant in ALS, FTD, or ALS/FTD, including SOD1, TARDBP, FUS, C9ORF72, MAPT, TBK1, BCP, GLE1, OPTN, UBQLN2, SQSTM1, ANG, TUBA4A, MATR3, VCP, and CHCHD10 [35]. The gene discussed is OPN1SW; the disease is frontotemporal dementia.