More than 20 years ago, mutation of the superoxide dismutase (SOD1) gene was identified as the major cause of the familial ALS [52], but other genes, such as fused in sarcoma (FUS), transacting response DNA-binding protein (TARDBP), and chromosome 9 open reading frame 72 (C9ORF72), were also shown to be accountable for the large percentage of familial ALS cases [53]. The gene discussed is C9orf72; the disease is amyotrophic lateral sclerosis.