Anti-GPC antibodies enable researchers to detect and measure the GPC antigen in biological samples. This target is a reported synonym of the GYPC gene, which encodes glycophorin C (Gerbich blood group). This protein is known to be a minor sialoglycoprotein in human erythrocyte membranes. The human version of GPC has a canonical amino acid length of 128 residues and a protein mass of 13.8 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the cell membrane of cells and notably expressed in many tissues, such as the kidney and testis. Other names for this target antigen include CD236, CD236R, and GE.