What is the primary function of the glycosyltransferase enzyme in the synthesis of ABO blood group antigens?

A To add fucose molecules to the antigen
B To add galactose molecules to the antigen
C To add N-acetylgalactosamine molecules to the antigen ✓
D To add sialic acid molecules to the antigen

Explanation

The glycosyltransferase enzyme is responsible for adding N-acetylgalactosamine molecules to the antigen, which determines the ABO blood group.

Source

Biochemistry of ABO Blood Group Antigens
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Hard MEDICAL Confidence: high