Presence of FTD hints possible mutations in ANG, TARDBP, OPTN, VCP, UBQLN2, CHMP2B, hnRNPA1, MATR3, or C9ORF72. Motor neuropathy involvement might occur in cases with mutations in SETX, VAPB, or FIG4. Complications of ataxia may be seen in cases with SOD1 or ATXN2 mutations. The gene discussed is SOD1; the disease is cerebellar ataxia.