Savagnin blanc (not pictured here) has been continuously propagated for at least 900 years.John Kolesidis / Reuters

In a medieval cesspit in central France, archaeologists dug up a small, hard grape seed. They believed it to be 900 years old, based on the artifacts found nearby. When geneticists crushed up the grape seed, extracted its DNA, and compared it with modern grapes, they found a perfect genetic match in Savagnin Blanc—a grape still grown, still picked, and still made into wine in Europe today.

This grape, it turns out, has survived unchanged for almost a millennium. In a time that has spanned the Hundred Years’ War, the Enlightenment, the French Revolution, Napoleon, and two world wars, someone has always thought to take cuttings of Savagnin Blanc to keep planting into the ground anew.

This technique is called vegetative or clonal propagation, and it’s a way to take a desirable variety and “freeze it across space and time,” says Sean Myles, an agricultural geneticist at Dalhousie University, who was not involved in the Savagnin Blanc study. Historical evidence suggests that viticulturists have been propagating grapevines this way for thousands of years, and the genetics now bears this out.

Nathan Wales, an ancient-DNA researcher at the University of York, and his collaborators came across the 900-year-old Savagnin Blanc among 28 grape seeds excavated from nine different archaeological sites around France. The seeds dated back to the medieval period, the Roman era (100 B.C. to 500 A.D.), and in one case even the Iron Age (500 B.C.). The team found six separate pairs or groups of genetically identical seeds, sometimes hundreds of miles apart. The clones had almost certainly spread through vegetative propagation by humans.

Waterlogged Roman grape seeds like these were genetically tested to investigate grape varieties in the past. (Laurent Bouby / CNRS ISEM)

One group of these Roman-era grape seeds were genetically similar, but not identical, to a modern variety called Mondeuse Blanche. In fact, Mondeuse Blanche appears to be the direct offspring of the Roman-era grapes. In other words, Wales says, “in 2000 years, there’s been one reproductive cycle between the Romans and today.” Grapevine varieties have stayed remarkably stable over the centuries.

The 900-year-old Savagnin Blanc—not to be confused with the more famous variety Sauvignon Blanc—is also notable because it is related to and probably even the parent of many modern varieties: Pinot Noir, Riesling Bleu, Verdejo, Sylvaner, Trousseau, and so on. “Savagnin, which to the general wine drinker is a very obscure minor grape, has this really important genetic history, and now we can take it back 1,000 years and put it in the middle of France,” says Jon Bonné, a wine writer and the author of the forthcoming The New French Wine. He likens the variety to the “Johnny Appleseed of all these other varieties.”

Savagnin Blanc is also known as Traminer Weiss, and it is still grown in a few European countries. But it is perhaps most famously used to make vin jaune or “yellow wine” from Jura in France. Vin jaune comes in a squat bottle called a clavelin and it has taken on a bit of a cult status. “It is probably the weirdest wine you’ll ever have,” Bonné says. “It is intensely yellow-colored. The best way I can describe it, it has almost no fruit characteristics. It’s nuts, almonds, and walnuts, and this very distinct, slightly acidic tang, too.”

While the grapes are genetically identical, Bonné says vin jaune is almost certainly not the same as the wine being made from Savagnin Blanc 900 years ago. The wine’s exact origins are lost to history, and vin jaune only became an official designation in the 20th century. “Despite some crafty marketing by the Jurassiens”—people of the Jura region of France—“it’s just hard to know what the historic expression of the wines really was,” Bonné added in an email.

The art of wine making—or perhaps wine selling—rests on the appeal of tradition. This is why grape varieties have continued to be propagated, frozen in name, time, and evolution. Meanwhile, the pathogens that prey on grapes have continued to evolve, leading to major pesticide use. “We could probably be breeding new grape varieties and not just relying on 1,000-year-old grape varieties,” Myles says. But, he adds, “it’s hard to go to Burgundy and say, ‘Here’s Sean’s new super grape.’ Are you going to strip out all your Pinot Noir and start planting Sean’s new super grape?” What’s the romance in that?

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