The function of Ensembl gene identifier ENSG00000158008 (EXTL1, exostosin like glycosyltransferase 1) is as follows. Glycosyltransferase required for the biosynthesis of heparan- sulfate (HS) (PubMed:11390981). Transfers N-acetyl-alpha-D-glucosamine to the nascent HS chain (GlcNAcT-II activity) (PubMed:11390981). Appears to lack GlcNAcT I and GlcAT-II activities (PubMed:11390981). .