NEK1 and amyotrophic lateral sclerosis: Notably, 29.2% of NEK1 carriers presented with a flail arm phenotype, a percentage significantly higher compared with non-NEK1 carriers of our ALS cohort, and with the 11% prevalence of this phenotype reported by previous studies (Wijesekera et al., 2009; Chio et al., 2011; Schito et al., 2020).