DMP1 and osteopetrosis: Recently, the involvement of osteocytes in osteoclastogenesis and bone resorption was reported using conditional knockout mice of β-catenin by Dmp1-Cre, which resulted in enhanced bone resorption, and conditional knockout mice of receptor activator of NF-κB ligand (Rankl) by Dmp1-Cre, which resulted in osteopetrosis [28], [29], [30].