This enzyme is the enzyme that synthesizes B antigen, which is the blood group carbohydrate antigen, encoded by the ABO gene. Its enzyme activity is a1,3-galactosyltransferase activity that transfers Gal from the donor UDP-Gal to the galactose residue of the non-reducing terminal of the acceptor (H type carbohydrate antigen) by an a1-3 bond.
B blood type
Histo-Blood group antigen
This page does not indicate all of the enzymatic reaction, and expression of "B(ABO)".