STXBP1 plays a non-redundant role in neurotransmission: genetic deletion of STXBP1 results in embryonic lethality in mice (19), and de novo mono-allelic mutations in humans invariably result in epileptic encephalopathy (a rare form of Dravet syndrome) (20). The gene discussed is STXBP1; the disease is Epileptic encephalopathy.