Matrix Gla protein (MGP) is an 84-residue vitamin K-dependent protein initially isolated from bovine bone. In addition, MGP is a 10-kD protein produced and secreted by vascular smooth muscle cells and chondrocytes and significantly accumulated in bone, cartilage, and dentin. It is also expressed at high levels in heart, kidney, and lung and is upregulated by vitamin D in bone cells. MGP has a high affinity binding to calcium ions, similar to other Gla-containing proteins. The protein acts as an inhibitor of vascular mineralization and plays a role in bone organization. And this gene is mapped to 12p12.3.