MeCP2 dysfunctions lead to a global alteration of the transcriptional program. (Left panel): In physiological conditions, both protein-coding and non-coding genes give rise to a variety of transcripts, some of which are expressed at high levels, whereas others are less abundant. Furthermore, the transcription rate of repetitive elements (including LINEs, intracisternal A particles and satellite DNA) is generally low. (Right panel): MeCP2 dysfunctions lead to the unbalanced production of both protein-coding and non-coding RNAs in both directions and to a general increased expression of repetitive elements.