GCNT4 (Glucosaminyl (N-Acetyl) Transferase 4, Core 2) is a Protein Coding gene. Among its related pathways are Mucin type O-glycan biosynthesis and O-linked glycosylation. Glycosyltransferase that mediates core 2 O-glycan branching, an important step in mucin-type biosynthesis. Does not have core 4 O-glycan or I-branching enzyme activity.