Furthermore, differential methylation in HOXA3 and/or HOXD3 have previously been observed in glia cells from DS fetal brains [44], peripheral blood leukocytes and fibroblasts of DS patients, and undifferentiated iPSCs with T21 [19, 47] suggesting dysregulated HOX genes to play an important role for a plethora of features characteristic for DS from early stages of development. This evidence concerns the gene HOXD3 and Dravet syndrome.