Pinot St. George
Pinot St George is actually the Negrette grape. A direct descendent of the Mavro grape from Cyprus, it has one of the clearest genetic ancestry's in the entire world of wine. It's even more rare for a French wine grape to hold that distinction since regions have typically allowed grapes to mutate at will in the vineyards over generations, often creating real differences in wine flavors imparted by grapes separated only by a small walking path.
Blends based are allowed to include up to 25% of an internatioanl varietal, historically that has been Cabernet Franc although changes in the marketplace has caused many vintners to begin using a higher amount of Cabernet Sauvignon.