FUT2 is an enzyme crucially involved in the synthesis of histo-blood group antigens and secretor status determination. Specifically, FUT2 catalyzes the transfer of fucose residues onto acceptor molecules, a process essential for the production of various glycoproteins and glycolipids found in bodily fluids and on the surface of epithelial cells. One of the most well-known substrates of FUT2 is the H antigen, which serves as a precursor for the ABO blood group antigens. The presence or absence of functional FUT2 determines an individual's secretor status, impacting the expression of certain blood group antigens in bodily fluids such as saliva and...