Remarkably, despite 20 years since the discovery that MECP2 loss of function mutations cause Rett syndrome, only a handful of putative target genes have been identified, and both the degree to which MeCP2 regulates these and the direction of dysregulation remain unclear (Amir et al., 1999; Na et al., 2013). The gene discussed is MECP2; the disease is atypical Rett syndrome.