SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy: In mice, loss-of-function Scn1a mutations caused clinical features reminiscent of Dravet syndrome, including early-onset epileptic seizures, hyperactivity, learning and memory deficits, reduced sociability and ataxic gaits and premature sudden death (Yu et al., 2006; Ogiwara et al., 2007; Oakley et al., 2009; Cao et al., 2012; Han et al., 2012; Kalume et al., 2013; Ito et al., 2013).