Gc-globulin is a multifunctional glycoprotein with a molecular mass of 51-58 kDa. It is also called vitamin D-binding protein (DBP). The main function of Gc-globulin is to bind vitamin D and actin, which is released into the extracellular environment upon cell and tissue lysis. Gc-globulin appears to have important clinical significance. Some investigation have shown that a low concentration of Gc-globulin may be used as a prognostic factor in patients with fulminant hepatic failure, acetaminophen (paracetamol) overdose, multiple trauma or multiple organ dysfunction syndrome (MODS), or sepsis. Many studies suggest an association between Gc-globulin phenotypes and resistance or susceptibility to chronic obstructive pulmonary disease (COPD), thyroid diseases, diabetes, multiple sclerosis, and sarcoidosis.