Interestingly, dysfunction of the POLR1A gene, which encodes the largest RNA polymerase I subunit, results in another clinically overlapping ribosomopathy—autosomal dominant acrofacial dysostosis, Cincinnati type (AFD-Cin), which can include highly variable degrees of mandibulofacial dysostosis, limb defects, and abnormal neurodevelopment [37]. This evidence concerns the gene POLR1A and mandibulofacial dysostosis.