Helping wheat make better bread.

• Position: Genetic Engineering - Brief Article

Average wheat varieties could be given superior bread-making qualities, thanks to genetic technology developed at the University of Florida's Institute of Food and Agricultural Sciences, Gainesville. "Traditionally, the bread-making characteristics of wheat differ from one variety to another," notes Indra Vasil, graduate research professor emeritus with the Department of Horticultural Sciences and leader of a group that developed the technology. "Wheat that's easy to grow doesn't always make good bread, but if it did we could save time and money."

Wheat's unique bread-making properties come from complex proteins called glutenins, found in no other cereal grain. Glutenins with high molecular weight (HMW glutenins) make stronger, more-elastic dough, which yields chewier bread. "By controlling HMW glutenins, we can have the best of both worlds. We can take a wheat variety that's very hardy and economical to grow but has poor bread-making qualities and turn it into a good bread-making wheat."

Wheat varieties used for bread have a genetic structure with three separate sets of chromosomes. Each set has one pair of genes that control HMW glutenins. "Theoretically, a wheat plant could have all six genes coding for HMW glutenins," Vasil points out. "But in nature it doesn't work that well. In most wheat varieties, only three to five of these genes are expressed."

He explains that traditional breeding methods have been ineffective at manipulating HMW glutenins, because the pairs of genes are so closely linked that the genes cannot be influenced individually. To solve the problem, Vasil devised a method to introduce a naturally occurring wheat gene, known as 1Ax1, into wheat plants. The gene is normally associated with production of HMW glutenins found in wheats that posess good bread-making qualities.

He and other University of...