Anti-MS antibodies enable researchers to detect and measure the MS antigen in biological samples. This target is a reported synonym of the MTR gene, which encodes 5-methyltetrahydrofolate-homocysteine methyltransferase. This protein is known to function in nervous system development, among other biological roles. The human version of MS has a canonical amino acid length of 1265 residues and a protein mass of 140.5 kilodaltons, although 2 isoforms have been identified. It is reported to be localized in the cytoplasm of cells and widely expressed in many tissue types. MS is a member of the Vitamin-B12 dependent methionine synthase protein family.