Gastric inhibitory polypeptide, or, GIP, is a human gene. Other names include: Glucose-dependent insulinotropic polypeptide; Incretin hormone. The encoded protein has an amino acid length of 153 and a mass of 17.1 kDa. Other isoforms may exist. Gastric inhibitory polypeptide is a member of the Glucagon family. This gene shares homology with other species, including: Mouse, Rat, Zebrafish, Frog, Chicken.