The draft genome sequence of Vitis vinifera, the grapevine, described in this issue, provides plenty of scope for discussion over a glass of its fermented product. The sequence was published online on 26 August and now appears in print (The French–Italian Public Consortium for Grapevine Genome Characterization Nature 449, 463–467; 2007).

The grape variety concerned is Pinot Noir, the classic red grape of Burgundy. But the vine sequenced does not produce exactly the same grape as that grown in the vineyards. The consortium chose to sequence a variety called PN40024, which has been bred by successive self-crossings to reduce the high degree of sequence variation that is characteristic of all grapevine varieties. The inbred strain allows efficient assembly of a high-quality sequence from whole-genome shotgun sequence data. In the shotgun technique the DNA is broken into many small fragments for sequencing and then reassembled from overlapping sequences.

The resulting genome sequence carries the imprint of millennia of selective breeding. For example, there are 116 genes and pseudogenes for terpene synthases, almost three times the number in the other three plant genomes so far sequenced. These enzymes synthesize the terpenoids that contribute to the aroma and flavour of wines, and pathways associated with tannins are similarly amplified.

Less obviously a target of selectivity are the genes that control the synthesis of resveratrol, the antioxidant credited with the health benefits claimed for moderate consumption of red wine. Yet there is a modest expansion, compared with the other sequenced plants, of the stilbene synthase genes associated with resveratrol synthesis.

Credit: WEGNER/NATURE PIC. LIB.

So can we look forward to genetically engineered 'designer' wines? Probably not. There is a market for new grapes, as exemplified by Cabernet Sauvignon clone 337, which is gaining ground in California's Napa Valley. But the flavour and aroma of wine depend on many other factors, such as growth conditions and production methods. And when it comes to producing wines with greater health-giving properties, the prospect sounds too good to be true. So it probably is. However, grapevines are notoriously susceptible to pathogens and stresses, such as drought, that other Vinus species can resist. The availability of this genome sequence should speed up progress on introducing the appropriate resistance into economically important varieties of V. vinifera.

With one grapevine genome sequenced, the way is clear for comparative oenogenomics. Yet when it comes to taste, perhaps the differences between a Pinot Noir with earthy and berry notes and a spicy or blowsy Gewürztraminer are best left to the realms of individual taste and a good thesaurus.