Call it a “family affair.” All commercial wine-producing grapevines, regardless of their variety, are produced from cuttings that are genetically identical to their original “mother” vine. But just like identical twins, they don’t always behave the same way.
In organisms such as grapevines, every time a cell divides, there’s the opportunity for spontaneous change to the genetic material, and many grape varieties with an ancient lineage have accumulated many mutations, producing all kinds of physical differences within the same variety. Some have seeds, some don’t; some have gold leaves, while some are green; some ripen early, and others don’t. In Montalcino, wine-makers boast that the Brunello vine is not the same plant as the sangiovese vine in Chianti. The grapes look different: The berries on Montalcino’s sangiovese grosso vines are larger than those on their northerly neighbors’ vines. Yet sangiovese and sangiovese grosso are genetically identical, and unquestionably the same variety.
Plants that carry identifiable mutations are called “clones” and, as the sangiovese example demonstrates, the choice of clone has a significant impact on the wine you drink. If you are one of those diehard red wine drinkers, who wouldn’t be caught dead drinking pinot grigio, you might want to consider that pinot grigio is nothing more than a mutation of pinot noir—one with just a different skin color.