In the subgroup analyses of men and those aged < 70 and ≥ 70 years, the ALS group had significantly higher CSF NSE levels than the CSM group (P < 0.001 for male patients, P = 0.001 for those aged < 70 years, and P = 0.002 for those aged ≥ 70 years) and the control group (P < 0.001 for male patients, P = 0.017 for those aged < 70 years, and P < 0.001 for those aged ≥ 70 years). This evidence concerns the gene ENO2 and amyotrophic lateral sclerosis.