Friday, September 3, 1999 Published at 07:54 GMT 08:54 UK
Inheriting the family nose
The humble Gouais grape bred modern classics
Some of France's most famous wine grapes are the product of a liaison between a noble red and a humble, down-and-out white.
The discovery by Carole Meredith and John Bowers from the University of California, Davis, will help avoid in-breeding between grape varieties.
Strong family links
Traditionally, grapevine varieties have been identified by physical features of their leaves and fruit. But these traits can vary according to environmental conditions.
Analysis of leaf samples from 300 varieties kept by the Institut de la Recherche Agronomique near Montpellier showed strong family links.
Further study of 60 samples revealed that 16 appear to come from just two ancient varieties - Pinot Noir and Gouais Blanc.
Grape spurned in Middle Ages
But the Gouais grape has been regarded as awful for centuries. Unsuccessful attempts were made to ban it from vineyards as far back as the Middle Ages, and it is no longer planted in France.
Even the name stems from an old French word "gou" - a term of derision.
The Gouais vine has a high yield of white grapes. Pinot Noir produces far less fruit, but of a higher quality.
Strength in diversity
"Gouais and Pinot have been successful parents because of their genetic diversity," said Professor Meredith.
"We now know you would never want to cross Chardonnay and Pinot, because you'd be more likely to get physically weak progeny, similar to in-breeding problems which occur when closely related people marry."
As well as being historically intriguing, the discovery has practical implications for conserving grape varieties.
The entire gene pool of all 16 grape types can be preserved just by keeping the Pinot and Gouais varieties.
The research is published in the journal Science.
Main picture: JP Bruno