Gluten-related disorders disease patients who have HLA-DQ2 and HLA-DQ8. Coeliac disease (American English: celiac) (CD) is one of the most common chronic, immune-mediated disorders, triggered by the eating of gluten, a mixture of proteins found in wheat, barley, rye and derivatives. Evidence has shown that this condition not only has an environmental component but a genetic one as well, due to strong associations of CD with the presence of HLA (Human leukocyte antigen) type II, specifically DQ2 and DQ8 alleles. These alleles can stimulate a T cell, mediated immune response against tissue transglutaminase (TTG), an enzyme in the extracellular matrix, leading to
Wheat allergy high molecular weight glutenin subunit, and similar proteins in other "Triticeae" genera, enter the blood stream during exercise where they cause acute asthmatic or allergic reaction. One recent study of ω-gliadins demonstrated these gliadins are more similar to the bulk of oat avenins than α/β or γ gliadins but, so far, oat avenins have not been linked to WDEIA. Wheat may specifically induce WDEIA and certain chronic urticaria because the anti-gliadin IgE detects ω-gliadins expressed by most of the Gli-B1 alleles, but prolamins extracted from rye or wheat/rye translocates invoke almost no responses. The Gli-B1 gene in wheat, "Triticum aestivum",