SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy: Dravet syndrome patient-iPSCs develop cardiac (Frasier et al., 2018) and neural (Higurashi et al., 2013) abnormalities in ways indicating neuronal hyperexcitability and predisposition for arrhythmia are caused by SCN1A haploinsufficiency.