RRM2 and amyotrophic lateral sclerosis: TDP‐43 has two RNA binding domains (RRM1 and RRM2) and a C‐terminal low complexity glycine‐rich domain (LCD), in which mutations causative for amyotrophic lateral sclerosis (ALS) are clustered (Ratti & Buratti, 2016; Ederle & Dormann, 2017).