Clinical studies showed that osteoclastogenesis was more frequently accelerated by diabetes mellitus: (a) enhanced levels of tartrate-resistant acid phosphatase, a sign of increased osteoclast activity, were found in the blood of patients with T2DM (66); (b) tartrate-resistant acid phosphatase levels were higher in blood among T2DM patients (67). This evidence concerns the gene ACP5 and type 2 diabetes mellitus.