Grenache Blanc - Grape Variety

There are two contenders for point of origin of the Grenache grape, both having seemingly equal claim: Sardinia has been growing this grape under the local name Cannonau for centuries, but whether longer than Garnacha has been cultivated in Spain is unknown. Grenache, like Pinot Noir, is prone to mutation and known "sports" include this, the white version, a pink-skinned version and a plant with hairy undersides to its leaves. Genetically these are all identical, something acknowledged in the laws of Châteauneuf-du-Pape, where Grenache Blanc is not considered a separate variety. Thus it could be said that rather than 13 permitted varieties in this appellation, there are actually 14 (15 if one includes Clairette Rose)!