SCN8A and Epileptic encephalopathy: Theoretically, this approach could benefit individuals with both loss-of-function (protein-truncating variants, missense, splice site) and severe gain-of-function (missense) variants and at least eight cases of epileptic encephalopathy have been identified with variants in 5A of SCN2A or SCN8A [13, 19, 57, 58].