SCN1A and developmental and epileptic encephalopathy: This suggested that the decreased excitability of GABAergic interneurons, induced by DS NaV1.1 epileptogenic variants, could reduce GABAergic inhibition and cause network hyperexcitability: it was one the first clear identifications of the pathologic mechanism of a DEE and the identification of NaV1.1 as the predominant Na+ channel of GABAergic interneurons.