The epilepsy gene map has been refined and extended with new information concerning benign familial neonatal convulsions, benign familial infantile convulsions, Unverricht-Lundborg disease, epilepsy with progressive mental retardation and juvenile myoclonic epilepsy. Understanding of the molecular basis of paroxysmal disorders affecting the central nervous system has been revolutionalized with the identification of mutations in genes for the neurotransmitter receptors, GLRA1 and CHRNA4, and a voltage-gated potassium channel, KCNA1, as causes of inherited neurological disease.