SCN1A and Dravet syndrome: Zebrafish larvae containing a single nucleotide substitution in the scn1lab gene were confirmed to have a loss-of-function in a sodium ion channel with 76% sequence identity to human SCN1A. In 2013, it was this scn1labs552 mutant zebrafish which we first described as replicating many of the essential clinical phenotypes observed in DS patients (Baraban et al., 2013).