Resumen de Cereals taxonomy: the role of domestication and breeding on gluten intolerance
María J. Giménez, Javier Gil Humanes, Juan B. Álvarez, Francisco Barro Losada
Storage proteins of wheat, rye, barley and, to a lesser extent, oatscontain epitopes responsible for triggering the celiac disease (CD). Inrecent decades an increased frequency of CD has been observed, andthough the reasons for this increase are unclear, modern plant breedinghas attracted criticism attributing to the new varieties a part of theresponsibility in worsening the data of prevalence. Wheat is one of themost important crops worldwide, presenting both high adaptability todifferent environments and yields. The domestication of wheat is theresult of a previous natural interspecific hybridization first betweendiploid, and then between diploid and tetraploid species that resulted inhexaploid wheat. The old farmers began to select the traits that werebetter adapted to the use. In the 20th century the wheat breeding had itsgreat advance and modern varieties were developed. The gliadin-relatedgenes, responsible for triggering CD, have no adaptive value andtherefore, if the toxicity of wheat was increased during the process ofdomestication and breeding this would have been made unconsciously.During the process of natural hybridization the number of gliadin-relatedgenes was increased. Bread wheat, rye, and Ae. tauschii have the highestnumber of CD epitopes per gene, and it seems that in bread wheat, thishigh number of epitopes is explained by the D genome from Ae. tauschii.During the process of domestication and breeding, the number of CDepitopes per gene did not increase and even decreased in some cases.
