SCN1A and familial hemiplegic migraine: Another mutation, Nav1.1-R1928G, is linked with cryptogenic epileptic syndrome [65], and characterized in patients diagnosed with generalized epilepsy with febrile seizures plus (GEFS+) [66], familial hemiplegic migraine (FHM) [67], and severe myoclonic epilepsy of infancy (SMEI) [68].