Peanut gene map to help combat food allergies

US researchers who recently completed the map of the peanut's genetic code are not just hoping to make peanuts more nutty but that the genetic blueprint will also help enhance disease resistance, cut down on pesticide use and increase the yield of the crop.

According to a report on Online Athens, the University of Georgia scientists who came up with the gene map believe it will pave the way towards a revolution in breeding the plant for better and cheaper varieties.

''I do think that agricultural genomes have maybe not been given sufficient priority,''​ said Andrew Paterson, director of the UGA Plant Genome Mapping Laboratory.

The peanut population mapped by Paterson and colleagues is a cross-breed of a commonly cultivated breed, the florunner, and a variety created synthetically with three wild peanut breeds. Using DNA-based technology, they developed genetic landmarks and determined how the landmarks are arranged within the 50,000 genes of the peanut genome. It is the first map of a common peanut variety and scientists hope to use it to help unravel what the genes do.

Food scientists studying peanut flavouring will be able to use the map to breed peanuts with a stronger peanut taste. In addition, and of particular interest today due to the increasing rise in human food allergies, the map will serve as a tool for working to suppress undesirable genes, such as those that trigger human allergies or a susceptibility in peanuts to the toxic aflatoxin fungus.

The peanut genome, or genetic material, is contained in 20 pairs of chromosomes found in each cell of the plant and the research took five years to complete.

''The human genome is not especially complex by the standards of plants,''​ Paterson said. ''We can identify plant genomes that are 20, 30, 50 times the size of the human genome. Peanuts and humans have similar quantities of DNA.''​

Due to the complexities of plant chemistry, it took a post-doctoral student eight months just to devise a technique for extracting DNA from peanut cells.

''Each plant has its own set of chemicals that protect against attack,''​ Paterson commented. ''When you try to fish DNA out we're literally attacking the cell. You can think of a plant cell as sort of tin can with a balloon inside. To get DNA of good quality we have to break the tin can but not the balloon.''​

But the work of unravelling the meaning of the genetic map will pick up speed, resulting in faster breeding, he said.

''There's a need to discover the spelling of all these genes,''​ he said. ''Once we know the spelling we can apply human genome technology ... to begin to understand what each of those (peanut genes) does, when it's turned on, when it's not. Once we get the spelling of the genes there's another century of work to figure out what they all do.''​