WASHINGTON, Aug 26 (Reuters) - Wine grapes have extra copies of genes that confer flavor and aroma, as well as extra DNA coding for a health-giving compound, researchers reported on Sunday.
The genome, or entire genetic map, of the grapevine sequenced by a collaboration of French and Italian scientists, shows the handiwork of master wine growers going back to the Stone Age.
They said their findings might lead to ways to identify the precise genes that give wine varieties their distinctive tastes and smells and may also lead to ways to breed disease-resistant grapes without sacrificing taste.
The French-Italian Public Consortium for Grapevine Genome Characterization sequenced the genome of Vitis vinifera, choosing a Pinot Noir variety.
"The draft sequence of the grapevine genome is the fourth one produced so far for flowering plants, the second for a woody species and the first for a fruit crop," they wrote in their report, published in the journal Nature.
"Grapevine was selected because of its important place in the cultural heritage of humanity beginning during the Neolithic period," added the team, led by Olivier Jaillon and Patrick Wincker of France's National Institute for Scientific Research at the Universite d'Evry.
Wine grapes have been bred for thousands of years, altered by generations of farmers and vintners seeking various qualities from sweetness to the dryness that tannins give.
The researchers noticed amplification -- which means extra copies -- of gene families like terpenes and tannins. These compounds give smells and flavor to plants.
"This suggests that it may become possible to trace the diversity of wine flavors down to the genome level," they wrote.
The researchers said the grapevine crop is "highly susceptible to a large diversity of pathogens including powdery mildew, oidium and Pierce disease."
But they said, "Other Vitis species such as V. riparia or V. cinerea, which are known to be resistant to several of these pathogens, are interfertile with V. vinifera and can be used for the introduction of resistance traits by advanced backcrosses or by gene transfer."
The researchers also found extra copies of genes involved in the production of resveratrol, the compound believed to give some of the noted health benefits to red wine.
