The remaining genetic causes of both ALS and FTD involve mutations in FUS and TARDBP (encoding TDP-43), which together account for ∼1% of all ALS cases, and a growing list of other genes linked to rarer familial forms (Abramzon et al., 2020; McCann et al., 2021). The gene discussed is FUS; the disease is amyotrophic lateral sclerosis.