SLC19A1 and Dravet syndrome: However, the over-expression of genes like GART (21q22.1, gene expression ratio=1.58), encoding for phosphoribosylglycinamide formyltransferase, phosphoribosylglycinamide synthetase, phosphoribosylaminoimidazole synthetase and SLC46A1 (17q11.2, gene expression ratio=1.67) and encoding for solute carrier family 46 member 1, and SLC19A1 (21q22.3, gene expression ratio=3.50), encoding for the solute carrier family 19 member 1, provides interesting hints about the hypothesis regarding the alteration of the one-carbon pathway in the manifestation of ID in DS [35, 36].