In wine there is truth, in vino veritas, as the ancient Romans put it. And the truth is that people first cultivated grapes for vino about 8,000 years ago, finds a genetics study.

In the current Proceedings of the National Academy of Sciences, a team led by Sean Myles of Cornell, looked at "1,000 samples of the domesticated grape, Vitis vinifera subsp. vinifera, and its wild relative, V. vinifera subsp. sylvestris." Comparing the gene maps across the grapes, the team concludes that humanity has only begun to explore the genetic diversity of the humble grape.

"Archaeological evidence suggests that grape domestication took place in the South Caucasus between the Caspian and Black Seas and that cultivated vinifera then spread south to the western side of the Fertile Crescent, the Jordan Valley, and Egypt by 5,000 y ago. Our analyses of relatedness between vinifera and sylvestris populations are consistent with archaeological data and support a geographical origin of grape domestication in the Near East. Grape growing and winemaking then expanded westward toward Europe, but the degree to which local wild sylvestris from Western Europe contributed genetically to Western European vinifera cultivars remains a contentious issue. Our results ... all support a model in which modern Western European cultivars experienced introgression from local wild sylvestris."

"Grapes are one of the world's most economically important fruit crops, and this study shows not only the potential for developing new approaches for improving existing varieties, but also the genetic relationships between many common varieties," said Edward Knipling, of the Agriculture Department, which sponsored the research, in a statement.

Earlier this week, a UCLA team reported archaeological evidence from an Armenian cave of the earliest known wine press, dating to 6,000 years ago.

The new analysis suggests that people have been conservative in crossing varieties, after the earliest domestication of wild grapes. The researchers call for genetically-guided cross-fertilization of grape varieties for increased hardiness. The lack of diversity in domestic grapes left wine-makers ripe for the attack of phylloxera root louse pests over a century ago that wiped out vineyards across France and Italy, impoverishing many families.