“…Gene mutations are the leading cause of ALS; however, the gene mutation profiles of classical ALS and JALS are different. For instance, mutations in SOD1, TDP-43, C9ORF72, FUS, ANG, OPTN, UBQLN2 , and ATXN2 have recently been identified in classical ALS, while mutations in FUS, SIGMAR1 , SPG11, ALS2, SOD1, C19ORF12, DDHD1, SETX , and TARDBP were detected in patients with JALS (Avemaria et al, 2011 ; Daoud et al, 2012 ; Siddiqi et al, 2014 ; Wu and Fan, 2016 ; Liu et al, 2017 ; Ma et al, 2018 ; Naumann et al, 2019 ). Whereas 90% of classical ALS cases are sporadic, the proportion falls to approximately 60% for JALS (Zou et al, 2016 ; Chen et al, 2020 ).…”