EXT1

EXT2 encodes exostosin glycosyltransferase 2, which is involved in the biosynthesis of heparan sulfate and heparin. The main structure of heparan sulfate is a repeating disaccharide structure consisting of (GlcNAcα1,4GlcAβ1,4)n, where sulfate is added to positions 2, 3, and 6 of GlcNAc and position 2 of GlcA and IdoA. EXT1 and EXT2 are responsible for the stretching reaction of the repeating disaccharide structure. EXT2 is also the causative gene of hereditary multiple exostoses (HME).