C-terminal telopeptide of type 1 collagen (CTX-1), osteocalcin (OC), N-telopeptide of type 1 collagen (NTX-1), procollagen type 1 N-terminal propeptide (P1NP), and tartrate-resistant acid phosphatase (TRAP) are reduced in T2DM patients [36]. This evidence concerns the gene ACP5 and type 2 diabetes mellitus.