C9orf72 and amyotrophic lateral sclerosis: About 10% of ALS cases are caused by identified mutant genes with inherited forms, such as chromosome 9 open reading frame 72 (C9orf72), copper/zinc superoxide dismutase 1 (SOD1) [2], and TARDNA-binding protein (TARDBP) [3], among which SOD1 is reported to be the most prevalent in Asian ALS patients (30%) [4].