The research findings published in the October 3, 2008 issue of Science are important because they clear the way for sequencing the wheat genome (Triticum aestivum L.). Wheat has huge economic importance because it is the staple food for 35% of the world's population. However, the tools for exploring the wheat genome are far less advanced than the tools developed for other cereals such as corn, rice, or sorghum. Both the size (17 billion base pairs, i.e., 5 times larger than the human genome and 40 times larger than the rice genome) and complexity (with more than 80% composed of repetitive sequences) of the wheat genome have been stumbling blocks to progress in the field.
The research was conducted as a pilot project within the framework of the International Wheat Genome Sequencing Consortium (http://www.wheatgenome.org). Thus, an international team headed by researchers at INRA Clermont-Ferrand, Toulouse and Versailles made the first step toward sequencing the larger wheat genome by drawing up the physical map of the largest chromosome, 3B that has nearly one billion base pairs. Their unprecedented feat is important because physical maps are priceless tools for rapidly locating genes with agricultural assets and for identifying new genetic markers. Physical maps make it possible to explore genome regions responsible for important agricultural traits, such as yield, quality and stress resistance.
The first application of the research: the scientists located some important genes, including a resistance gene to stem rust, a major fungal disease, on the physical map of chromosome 3B.
