TILLING Wheat for Reduced Celiac Disease Causing Proteins

DESCRIPTION (provided by applicant): Celiac disease is an autoimmune digestive disorder in which intestinal lesions develop in genetically susceptible individuals in response to the ingestion of specific seed storage proteins found in cereal grains. The only treatment is strict adherence to a diet from which the offending grains have been eliminated. Therefore, considerable research has been devoted to identifying the specific amino acid sequences in wheat seed storage proteins responsible for eliciting the immune reaction in celiac patients, and this research has motivated the hope that strains of wheat and other grains could be developed in which these proteins have been reduced or eliminated. Anawah has successfully developed a novel, non GMO (genetically modified organism) target-selected mutation breeding approach called TILLING (Targeting Induced Local Lesions in Genomes). In collaboration with Dr. Diter von Wettstein of Washington State University, we will apply TILLING to develop lines of wheat in which some of the gliadins, which are believed to be the most potent antigens responsible for celiac disease, have been modified or eliminated. This NIH STTR Phase I proposal will result in novel lines of wheat that will serve both as research tools to genetically define the most potent elicitors of the lesions found in celiac disease patients as well as sources of novel germplasm that will form the basis of Phase II research and development aimed at producing varieties of wheat that lack prominent disease causing autoimmunogenic epitopes in the gluten. The objective of our Phase I STTR propsal will be met with the following specific aims: 1. Design PCR primers, based upon the available wheat gliadin DNA sequences, to specifically amplify, from genomic DNA of tetraploid pasta wheat, subsets of the gliadins that are believed to be the most toxic to celiac disease patients. 2. Use these primers to identify null and missense alleles of these genes in our wheat TILLING library of genetic variants. 3. Prioritize plants containing new alleles of the targeted gliadins for marker-assisted crossing. 4. Using a variety of methods including 2D PAGE of seed endosperm proteins, we will begin phenotypic characterization of the progeny of the plants containing the high priority induced alleles that we identify.