MECP2 and attention deficit-hyperactivity disorder: Complementing the relevance of altered MeCP2 expression to neurodevelopmental disorders and the multigenerational consequences of DNE, atypical MeCP2 (Ser421) phosphorylation hinders neurodevelopment, experience-dependent chromatin remodeling, dendritic outgrowth and spine maturation, and BDNF expression, resulting in anomalous behavioral phenotypes which are concordant with ADHD, autism, schizophrenia, and smoking during pregnancy [118–120].