SCN8A and Epileptic encephalopathy: Most of the pathogenic SCN8A variants are associated with severe epileptic encephalopathy (Blanchard et al., 2015; Larsen et al., 2015; Wagnon et al., 2016; Butler et al., 2017; Gardella et al., 2018; Johannesen et al., 2018; Brunklaus et al., 2020); however, milder phenotypes associated with missense variants have also been reported (Gardella et al., 2016; Rossi et al., 2017; Liu et al., 2019).