Apart from C9ORF72 hexanucleotide (GGGGCC) repeat expansion, representing the most common genetic cause of both familial and sporadic ALS, decreased C9ORF72 mRNA levels were found in patient-derived cells and tissue; the deletion of this gene locus leads to disruption in endosomal trafficking, synaptic vesicle function, regulation of the actin cytoskeleton, and formation of autophagosome, resulting in MN degeneration [19,20]. The gene discussed is C9orf72; the disease is amyotrophic lateral sclerosis.