RUNX2 and cleidocranial dysplasia 1: Here, we examined alveolar bone cells, which served as a representative model for the bone defects commonly found in patients with CCD, and demonstrated that aBMSCs from a patient with the p.Ser247Valfs*3 exhibited reduced RUNX2, OCN, and COL1A1 expression compared with controls, However, the expression of ALP was comparable between CCD cells and the control cells.