GABRB3 and Dravet syndrome: Here, were report a girl affected by DS presenting two de novo heterozygous mutations, a missense variant on GABRB3 gene (c.842 C>T; p.Thr 281Ile) and a nonsense variant (c.883 C>T;p.Arg295Ter) on BBS4 gene (OMIM: 600374).