Based on studies in mice, MECP2 represses transcription from the CRH gene promoter (McGill et al. 2006). Mice with the loss of function of Mecp2 exhibit overexpression of Crh (McGill et al. 2006). Surprisingly, mice with Mecp2 gene duplication, which serve as a model for the MECP2 duplication syndrome, also overexpress Crh (Samaco et al. 2012).