RNF146 and cleidocranial dysplasia 1: In addition to the roles of RNF146 in osteoclastogenesis and cytokine production, we have provided further genetic evidence showing that mice lacking RNF146 in osteoblasts show phenotypic similarities to cleidocranial dysplasia (CCD) (55), an autosomal dominant human disorder characterized by abnormal bone development mainly due to defective intramembranous bone formation by osteoblasts (56, 57).