Coeliac disease disease genotypes. It is suspected that some of them may have been beneficial by providing protection against bacterial infections. The majority of the proteins in food responsible for the immune reaction in coeliac disease are the prolamins. These are storage proteins rich in proline ("prol-") and glutamine ("-amin") that dissolve in alcohols and are resistant to proteases and peptidases of the gut. Prolamins are found in cereal grains with different grains having different but related prolamins: wheat (gliadin), barley (hordein), rye (secalin) and oats (avenin). One region of α-gliadin stimulates membrane cells, enterocytes, of the intestine to allow larger molecules
Wheat allergy comes from the progenitor species "Aegilops speltoides". This indicates that nascent mutations on the B genome of wheat are from a small number of cultivated Triticeae species. Recent study of WDEIA shows that both aspirin and exercise increase the presence of gliadin in the blood stream and the chronic induced response may extend to NSAIDs, MSG, Benzoate and other synthetic chemical food additives. Baker's allergy has a ω-gliadin component and thioredoxin hB component. In addition, a gluten-extrinsic allergen has been identified as aspergillus amylase, added to flour to increase its baking properties. Contact sensitivity, atopic dermatitis, eczema, and urticaria appear