In Science this week, international research teams reports the construction and analyses of a fully annotated reference genome for bread wheat. In one study, the International Wheat Genome Sequencing Consortium (IWGSC) publishes the first high-quality fully annotated reference genome sequence of the bread wheat cultivar Chinese Spring, providing the location and organization of over 107,000 genes and more than 4 million markers across all of the variety's 21 chromosomes. In a second study, researchers use the IWGSC reference genome to examine homoelog expression across a range of wheat tissues, developmental stages, and cultivars. They show that homoelog expression patterns in bread wheat "have been shaped by polyploidy, and are associated with both epigenetic modifications and variation in transposable elements within promoters of homoelogous genes." The findings provide a framework for targeting genes in wheat implicated in agronomic traits.
Finally, in Science Advances, members of the IWGSC and others use the new wheat reference genome to investigate the proteins involved in wheat-related immune responses and clinical manifestations. Among their findings are that genes linked to celiac disease and wheat-dependent exercise-induced anaphylaxis (WDEIA) are expressed in the starchy endosperm, and that temperature stress during flowering can increase the levels of major celiac and WDEIA proteins. "The study establishes a new reference map for immunostimulatory wheat proteins and provides a fresh basis for selecting wheat lines and developing diagnostics for products with more favorable consumer attributes," the researchers conclude.
GenomeWeb has more on the wheat genome and related studies here.