Deciphering wheat

Wheat (Photo credit: Wikipedia)

The first analysis of the complex and exceptionally large bread wheat genome, published on 29 November in the journal Nature, is a major breakthrough in breeding wheat varieties that are more productive and better able to cope with disease, drought and other stresses that cause crop losses.

The study, led by researchers in the UK, US and Switzerland, identifies around 96,000 wheat genes and delves into the links between them. The new findings lay strong foundations for accelerating the improvement of one of the world’s most important crops, and the production of new wheat varieties. Published just two years after researchers finished generating the sequence, the analyses will contribute directly to improving food security.

The team sifted through vast amounts of DNA sequence data in order to translate the sequence into useful information for research scientists and plant breeders. They made rapid progress by developing a new strategy that compared wheat’s genetic sequences to known grass genes (for example from rice and barley), and comparing these to the simpler genomes of wheat’s ancestors. This revealed a highly dynamic genome that has undergone genetic loss as a consequence of domestication.

All of the data and analyses are freely available to everyone through EMBL-EBI’s Ensembl Plants.

“Bread wheat is a complex hybrid, composed of the complete genomes of three closely related grasses,” said Klaus Mayer of the University of Liverpool in an announcement issued by the Biotechnology and Biological Sciences Research Council. “This makes it very complex and large; in total it is almost five times bigger than the human genome. Because of this, we took a novel approach to analysing the data, and we have been successful in turning it into accessible and useful resources that will accelerate breeding and the discovery of varieties with improved performance - for example better disease resistance and stress tolerance.”

"The wheat genome is among the final frontiers of genomics and is of tremendous importance to food supplies in Europe and worldwide,” said Paul Kersey, Head of Ensembl Genomes at EMBL-EBI. “This assembly is a significant step towards deciphering the wheat genome and the data can be visualised, in the context of a reference grass sequence, through Ensembl Plants.”

“In the face of this year’s wheat crop losses, and worries over the impact on prices for consumers, this breakthrough in our understanding of the bread wheat genome could not have come at a better time,” said Professor Douglas Kell, BBSRC Chief Executive. “This modern strategy is a key component to supporting food security and gives breeders the tools to produce more robust varieties with higher yields. It will help to identify the best genetic sequences for use in breeding programmes.”

The research was made possible by major funding from the BBSRC, the EU and the National Science Foundation in the US.

Source article

Brenchley, R., et al. (2012) Analysis of the bread wheat genome using whole-genome shotgun sequencing. Nature 491, 705–710; doi: 10.1038/nature11650