Anti-RJD9 antibodies enable researchers to detect and measure the RJD9 antigen in biological samples. This target is a reported synonym of the GNPTG gene, which encodes N-acetylglucosamine-1-phosphate transferase subunit gamma. This protein is reported to be a non-catalytic subunit of the N-acetylglucosamine-1-phosphotransferase complex, an enzyme that catalyzes the formation of mannose 6-phosphate (M6P) markers on high mannose type oligosaccharides in the Golgi apparatus. The human version of RJD9 has a canonical amino acid length of 305 residues and a protein mass of 34 kilodaltons. It is reported to be localized in the Golgi and is secreted of cells and widely expressed in many tissue types.