Post hoc analysis of Dunn’s multiple comparison tests revealed significantly higher levels of CSF TDP‐43 in the ALS group compared with those in the CIDP subgroup, CSF NfL in the ALS group compared with those in the CIDP and GBS subgroups, and CSF t‐tau in the ALS group compared with those in the CIDP subgroup. This evidence concerns the gene NEFL and amyotrophic lateral sclerosis.