Four of them, Nav1.1 Nav1.2, Nav1.3 and Nav1.6, encoded by SCN1A, SCN2A, SCN3A and SCN8A genes, respectively (OMIM; 182389, 182390, 182391, 600702), are involved in the pathogenesis of different forms of epilepsy/developmental and epileptic encephalopathies (OMIM; DEEs Phenotypic Series-PS308350). This evidence concerns the gene SCN1A and Epileptic encephalopathy.