Based on these findings, we speculate that importin β disruption may contribute to pathological protein mislocalization in C9orf72-mediated ALS/FTD, including TDP-43, for which links to downstream neurodegeneration are beginning to be unraveled (Ling et al., 2015; Melamed et al., 2019; Klim et al., 2019). This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.