Syndromes in which a clear association between defective ribosome biogenesis and NCC loss has been identified, include Treacher Collins syndrome (Dauwerse et al., 2011; Bowman et al., 2012), postaxial acrofacial dysostosis (Trainor and Merrill, 2014), acrofacial dysostosis – Cincinnati type (Weaver et al., 2015), Diamond Blackfan Anemia (Narla and Ebert, 2010), and Roberts syndrome (Xu et al., 2014). This evidence concerns the gene SLC12A3 and postaxial acrofacial dysostosis.