SCN1A and Sudden unexpected death in epilepsy: Sudden unexpected death in epilepsy (SUDEP) is known to occur, possibly because of lethal cardiac arrhythmias following severe seizures in Scn1a knock-in R1407X DS mouse model (Auerbach et al., 2013) and Scn1a+/− knock-out DS mouse model (Kalume et al., 2013).