This gene encodes a member of the galactose-3-O-sulfotransferase protein family. The product of this gene catalyzes sulfonation by transferring a sulfate to the C-3' position of galactose residues in O-linked glycoproteins. This enzyme is highly specific for core 1 structures, with asialofetuin,
Gal-beta-1,3-GalNAc and
Gal-beta-1,3 (GlcNAc-
beta-1,6)GalNAc being good substrates. [provided by RefSeq, Jul 2008]