TARDBP and amyotrophic lateral sclerosis: Significantly, RNA processing defects, such as intron retention (Luisier et al., 2018) and mRNA instability (Tank et al., 2018), have been observed in FUS or TDP-43 fALS as well as sALS MN, indicating that ALS models harboring these mutations may provide insights into the molecular mechanisms of both fALS and sALS.