Genes show wine's pedigree
2007-08-27 13:23
Washington - Wine grapes have extra
copies of genes that confer flavour 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
Characterisation 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 flavour to plants.
"This suggests that it may become possible to trace the
diversity of wine flavours 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.
- Reuters