Anti-GalNAc-T5 antibodies are used in antigen-specific immunodetection in biological samples. The target GalNAc-T5 is a known alias name of the protein polypeptide N-acetylgalactosaminyltransferase 5, encoded by the GALNT5 gene in humans. This 940-amino acid residue protein is known to catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. It is localized to the Golgi of the cell and features glycosylated post-translational modifications. It is reported to be expressed in many tissues, such as the appendix and colon.