These signaling pathways include the extracellular signal-regulated kinase (ERK) pathway and the mammalian target of rapamycin (mTOR) pathway, both of which are deregulated in FXS (Huber et al., 2001; Sharma et al., 2010; Hoeffer et al., 2012; Wang et al., 2012). This evidence concerns the gene MTOR and fragile X syndrome.