Some SCN1A mutations that lead to either Dravet syndrome (DS) or GEFS+ epilepsy have been correlated with premature death in mouse models (Yu et al., 2006; Ogiwara et al., 2007; Martin et al., 2010). This evidence concerns the gene SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.