SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy: The first involves the SCN1A gene, known to be associated with several autosomal dominant epileptic disorders (e.g., Dravet syndrome–MIM: #607208–, Developmental and epileptic encephalopathy 6b–MIM: #619317–, and Generalized epilepsy with febrile seizures plus, type 2–MIM: #604403).