For plasma NF-L levels, ROC analysis indicated an AUC value of 0.98 ± 0.01405 (95% CI 0.95–1.00, P = 0.000) when comparing amyotrophic lateral sclerosis and HC cases, with the optimal cut-off at 29.03 pg/mL determined by the Youden index (0.865; sensitivity of 86.5%; specificity of 100%; Fig. 2D). This evidence concerns the gene NEFL and amyotrophic lateral sclerosis.