gammagliadin

Gammagliadin, more commonly written gamma-gliadin, is a type of gluten protein belonging to the gliadin family found in wheat. It is a prolamin, rich in proline and glutamine, and is soluble in alcohol–water solutions. Gamma-gliadins are seed-storage proteins produced in the wheat endosperm and are part of the gluten complex that contributes to dough viscosity and extensibility.

Genetics and variation: Gamma-gliadin peptides are encoded by multigene families within the wheat genome, with multiple variants across cultivars. The exact composition of gamma-gliadins varies by wheat species and variety, influencing gluten quality and immunogenic potential.

Health relevance: In celiac disease, certain gamma-gliadin-derived peptides can trigger an adaptive immune response after modification by tissue transglutaminase, with presentation by HLA-DQ2 or DQ8 molecules leading to T cell activation. While alpha-gliadins are often the most immunotoxic, gamma-gliadins can contribute to the disease process. Gamma-gliadins may also be involved in other gluten-related disorders and wheat allergies, though individual sensitivity varies.

Food and nutrition: Because gamma-gliadin is part of gluten, products made from wheat containing gamma-gliadin are not suitable for a gluten-free diet. In gluten-free formulations, producers remove or reduce all gluten proteins, including gamma-gliadins, through suitable processing or ingredient choices.

Notes: The term gammagliadin is a less common spelling; gamma-gliadin is the standard term in scientific literature.