A number of genes classified as transcriptional or epigenetic regulators have been implicated in ASDs (Network and Pathway Analysis Subgroup of Psychiatric Genomics Consortium, 2015). These genetic findings support a molecular mechanism involving transcriptional regulation underlying the pathogenesis of ASDs. One of the best characterized genes in this category is MECP2, a gene encoding a methylated DNA-binding protein (Amir et al., 1999; reviewed in Lyst and Bird, 2015). Although the protein was characterized as a transcriptional repressor when it was first identified (Nan et al., 1997), data from more recent studies indicate that MeCP2 acts as a global transcriptional regulator involved in both the suppression and activation of targeted genes (Chahrour et al., 2008; Ben-Shachar et al., 2009), as well as a regulator of RNA splicing (Young et al., 2005; Maunakea et al. 2013).
