In order to get further insights into the contribution of IEGs hyperactivation on the RTT phenotype and taking into account, (i) such as in other neurological disorders, RTT displays glial abnormalities, with myelination being altered in Mecp2-KO mice [48,49] and (ii) EGR2 is highly expressed in Schwann cells and oligodendrocytes and is a master regulatory gene for myelination through partnering with NAB proteins [50,51] (Figure 6a), we next explored the expression of key markers of the myelin production pathway in the mouse and human RTT samples (Figure 6b,d). The gene discussed is EGR2; the disease is nervous system disorder.