The proteomic approach used in the present study provided us with a broader picture of the proteins involved in the pathophysiological process of osteopenia/osteoporosis, leading to the identification of VDBP and other previously described proteins, such as apolipoprotein AI [47], ceruloplasmin, kininogen 1 [47], alpha-2-HS-glycoprotein [28,29], serpin A1, and serpin A3 [30]. The gene discussed is SERPINA1; the disease is osteoporosis.