As aforementioned, overexpression of miR-155 and miR-802 have been found to repress MeCP2 expression (Kuhn et al., 2010), therefore these HSA21-miRNAs in DS brain are expected to repress MeCP2 and subsequently relieve the suppression on miR-199b and decreased SIRT1 expression. This evidence concerns the gene MECP2 and Dravet syndrome.