Fig. 3.

Multiple congenital anomaly syndromes having clinical overlap with CHARGE syndrome and 22q11.2 microdeletion syndrome. In figure 3, we show the overlapping clinical features of CHARGE and 22q11.2 deletion syndrome with known genetic syndromes. All the genes mentioned in this figure or their proteins have been associated with either CHD7 or TBX1. The expression of FGFR1, OTX2 and TBX1 depends on CHD7 in some tissues; TBX1 and FGF8 are in epistasis in ectodermal development; binding of the protein treacle which is encoded by TCOF1 partly depends on the presence of CHD7, and SOX2 and CHD7 are cofactors that regulate the expression of JAG1, MYCN and GLI3, amongst others [Randall et al., 2009; Hurd et al., 2010; Zentner et al., 2010a; Engelen et al., 2011; Layman et al., 2011]. Figure 3 shows that the linked molecular pathways are reflected by the shared clinical features of the syndromes.