TBK1 and frontotemporal dementia: To date, based on the definition of the Online Mendelian Inheritance in Man [60], 5 ALS-FTD genes—namely, C9Orf72 [61], CHCHD10 [62], SQSTM1 [63], TBK1 [64], and CCNF [65]—have been recognized along with roughly 30 genes associated to ALS-FTD.