Partially Purified. CA-125 also known as mucin 16 or MUC16 is a protein that in humans is encoded by the MUC16 gene. MUC16 is a member of the mucin family of glycoproteins. CA-125 has found application as a tumor marker or biomarker that may be elevated in the blood of some patients with specific types of cancers, or other benign conditions. Source: Native CA 125, from human pleural or ascites fluids. Applications: Suitable for use for making standards, calibrators, and is primarily used for multiple analyte controls.