Previous studies demonstrated that the average interictal NF-L levels in patients with drug-refractory epilepsy due to structural and other etiologies, genetic epilepsy, or temporal lobe epilepsy with hippocampal sclerosis are comparable to those in controls, although they can be slightly increased in some subpopulations of patients when using a cut-off level of 10 pg/mL [51,52,53]. This evidence concerns the gene NEFL and epilepsy.