Wheat genome finally reveals its secrets

Globally, wheat is one of the most important staple crops, providing a fifth of daily calories across the world.

As such a huge contributor to the global food supply, it is vital that wheat yields increase if global food security is to be ensured into the future. Indeed, the Food and Agriculture Organisation of the United Nations has calculated that global crop yields will need to be doubled by 2050.

However, crop yields have remained fairly stagnant since the mid-1990s. It is hoped that sequencing the wheat genome will give agronomists insight and facilitate the development of higher yielding cultivars.

This sequencing has not been straightforward. With 17 billion bases, the wheat genome is five times larger than the human genome and has a hexaploid structure. Also, nearly 80% of the genetic material is repetitive, making it even harder to sequence and analyse. 

Now the genome has finally been sequenced by an international team led by Matthew Clark, head of of technology development at the Earlham Institute, and including scientists from the ARC Centre of Excellence in Plant Energy Biology (University of Western Australia), John Innes Centre, European Bioinformatics Institute, Rothamsted Research and Plant Genome and Systems Biology, Helmholtz Center Munich. 

The sequencing of the bread wheat genome identified complete sets of genes and proteins essential to important agronomic traits, including the location and detailed annotation of over 100,000 wheat genes. More than a fifth (22%) of these were either completely absent from earlier assemblies or found only as fragments. The work has been published in Genome Research.

The UWA researchers led the protein analysis research that provided direct evidence that many of the genes coded for molecular machinery important for wheat growth and development, protection of wheat from diseases and resistance to harsh environments.

Over 1000 wheat disease-resistance genes and their locations in the genome were revealed by the study. The knowledge will greatly aid marker-assisted breeding of wheat disease traits. Also identified were over 100 gluten genes, the analysis of which will be vital to changing gluten content in wheat.