Forty-six genes that are related to FTD, ALS, or other dementias were screened for pathogenic variants: ALS2, ANG, CHMP2B, CHRNA4, DAO, DCTN1, FIG4, FUS, GRN, HNRNPA1, HNRNPA2B1, MAPT, MATR3, OPTN, PRNP, SETX, SIGMAR1, SOD1, SPG11, SQSTM1, TAF15, TARDBP, TBK1, TREM2, UBQLN2, VAPB, VCP, AARS2, ABCD1, APP, ARSA, CSF1R, DARS2, EIF2B1, EIF2B2, EIF2B3, EIF2B4, EIF2B5, GALC, GBA, GLA, NOTCH3, PSEN1, PSEN2, SNCB, and TYROBP. We did not identify likely pathogenic variants or pathogenic variants in dementia-related genes in the two FTD patients. The gene discussed is OPTN; the disease is amyotrophic lateral sclerosis.