In this study, we showed that Mecp2 expression is epigenetically regulated during brain development via miR-26b, and that deregulation of miR-26b-Mecp2 in NSCs and synaptogenesis in differentiating neurons derived from embryos of diabetic pregnancy may underlie neurodevelopmental disorders associated with maternal diabetes (Figure 6). The gene discussed is MECP2; the disease is neurodevelopmental disorder.