KCNQ2 and Benign familial neonatal seizures: Benign familial neonatal seizures (BFNS) as another early-onset epilepsy have been revealed to be associated with loss-of-function mutations of voltage-gated potassium channel genes, including KCNQ2 (potassium voltage-gated channel subfamily Q member 2) and KCNQ3 [84].