Clobazam, as the first-line drug therapy treating epilepsy associated with SCN1A mutations, which increases transmission of postsynaptic GABAergic signals with allosteric modulation of GABAA receptors; and VPA, which increases GABA concentration in the synaptic gap through enhancement of GABA production and reduction of GABA degradation. The gene discussed is SCN1A; the disease is epilepsy.