MECP2 and Rett syndrome: We were able to observe Mecp2 expression in epithelial cells from the lower part of the colon crypts, but the selective Mecp2 knockdown in intestinal epithelium did not recapitulate the observed features of the Mecp2-null mice, suggesting a complex interaction between different tissues expressing Mecp2 that participates in the development of the multisystemic complaint including intestinal symptoms in RTT patients.