From Sydney Morning Herald 15/1/08:

Fancy a drop of red? How about a zinfandel-plavac mali blend?

A researcher in Europe has shed new light on the parentage of the viognier grapevine and concluded that DNA testing could result in some new ideas for blending grape varieties. Dr Jose Vouillamoz, working at in institute in Trentino, Italy, and a university in Neuchatel, Switzerland, has shown that viognier and syrah are related, which may explain why they work so well together in blends. Small percentges of viognier are blended with syrah in red wines of Cote-Rotie in France and other parts of the world such as Australia.

Vouillamoz says: “Interestingly, some of the best wine grape blends often involve related cultivars: cabernet franc and its progenies cabernet sauvignon and merlot in Bordeaus, syrah and its half-brother (or grandfather) viognier in Cote-Rotie, sangiovese and its father ciliegiolo in Chianti, nebbiolo and its progeny nebbiolo rosé in Barolo. Paternity research discoveries could thus provide new ideas for successful blends, such as syrah with its father dureza, of which there’s less than a hectare planted in the Ardeche (France), or zinfandel with its Croatian son plavac mali.”