The gene-set collapsing analysis revealed an enrichment (P = 0.010) of rare variants in Dravet syndrome (78 variants in 28 individuals; 2.78 variants per individual) compared with GEL SCN1A controls (81 variants in 45 individuals; 1.8 variants per individual). This evidence concerns the gene SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.