C9ORF72 mutations: The hexanucleotide repeat expansion (GGGGCC (G 4 C 2)) (HRE), located in the first intron of the C9ORF72 gene, has been related to the pathogenesis of ALS, as it has been seen that these expansions generate a long RNA that sequesters RNA-binding proteins, promoting the formation of other protein inclusions, such as TDP-43 [57]. This evidence concerns the gene C9orf72 and amyotrophic lateral sclerosis.