Cracking the corn code could unlock nutritional value

Plans to unlock the genetic code of the corn plant could help lead to higher yields and better quality ingredients.

Most recently, researchers at the University of Arizona (UA)'s plant sciences department and UA's BIO5 Institute received a $29 million federal grant as part of the Maize Genome Sequencing project.

The initiative aims to help the food sector to improve important traits in cereal crops more rapidly.

One important goal is to enhance drought resistance in corn and other cereal crops, which would greatly benefit regions with less favourable conditions for agriculture. Other improvements aim at increasing yield and nutritional value and optimising the properties crucial for grain products such as flour, noodles and pasta.

Unravelling the corn genome will also have enormous implications for other cereal crops besides corn, including wheat, sorghum and millet.

"A lot of applications will result from this project," said Brian Larkins, a Regents' Professor in the department of plant sciences who works on enhancing the nutritional value of corn. "The cereals are very closely related to each other, so we can transfer a lot of what we learn about gene function in maize to other crops."

Corn is one of the most important economic crops, and, together with rice, accounts for 70 percent of worldwide food production. The production of corn-based products with enhanced nutritional value that are safer and less allergenic will directly benefit consumers.

And with the world's population rapidly heading for the 7 billion mark, feeding everyone is a growing problem that has to be tackled now.

The purpose of the Maize Genome Sequencing project is therefore to unravel the complete DNA sequence of the maize plant and to determine the number of genes and their position on the chromosomes - the tiny bundles of DNA that form the storage units of genetic information.

Using a physical map that covers about 95 per cent of the maize genome map, scientists will generate a draft sequence to reveal the locations of the genes within stretches of so-called non-coding DNA. Only the gene-containing regions will then be sequenced in detail.

This sequencing strategy will enable the consortium to sequence the corn genome at a fraction of the cost that was necessary to decipher the human genome, which is only slightly larger than the corn genome.

The UA team previously collaborated with Washington University and Cold Spring Harbor Laboratory as part of an international consortium to unravel the rice genome sequence, which was published in Nature in August 2005.