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.
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.