GCNT1 (Glucosaminyl (N-Acetyl) Transferase 1): GCNT1 is a gene that encodes an enzyme involved in the biosynthesis of mucins, key components of mucus. It contributes to the modification of glycoproteins, influencing cell signaling and immune function. Altered GCNT1 activity has been linked to conditions such as cystic fibrosis and certain cancers.