This congenital disorder, also known as Marie-Sainton disease or cleidocranial dysostosis, arises from mutations in the Runt-related transcription factor 2 (RUNX2 gene; previously known as core binding factor subunit alpha or CBFA1) located on chromosome 6p21 [2]. The gene discussed is RUNX2; the disease is cleidocranial dysplasia 1.