The commonest cause is structural brain abnormality, this may be an acquired brain abnormality, or due to de novo gene abnormalities.
Genetic etiologies include: KCNQ2, SCN2A, STXBP1, CDKL5, KCNT1 and others.
Family history of seizures or epilepsy is usually not present. A positive family history should trigger a search for a genetic or metabolic etiology.