IRX5 and Craniofacial dysplasia-osteopenia syndrome: Two mutations in human IRX5, Ala150Pro and Asn166Lys occur in patients with Hamamy syndrome (OMIM MIM611174; Bonnard et al., 2012), who present with craniofacial dysmorphism, osteopenia, tooth eruption defects, and hip dysplasia, along with cardiac defects and microcytic hypochromic anemia (Bonnard et al., 2012, Hamamy et al., 2007a, Hamamy et al., 2007b).