ATXN2 and amyotrophic lateral sclerosis: The molecular genetic pathogenesis of ALS is advancing with the recent discovery of many gene mutations in ALS patients, many of which encode RBPs, such as TDP-43, FUS, ataxin 2, TATA box binding protein-associated factor 15 (TAF15), ewing sarcoma breakpoint region 1 (EWSR1), heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), hnRNPA2/B1, matrin3 (MATR3) and T cell-restricted intracellular antigen-1 (TIA-1) (Figure 3).