Chanton, Gwäss 2004 Vispertal, Valais/Wallis

This week's selection is for those (few?) wine lovers who are as fascinated as I am by grapevine genetics, or the history of the vine varieties which now rule the wine world. As many of you will know, DNA profiling techniques have shed unexpected shafts of light on the complex web of relationships between different varieties in recent years. Thanks to comparing the detail of the genetic make-up of various Bordeaux varieties, for example, we now know that Cabernet Sauvignon is the progeny of Cabernet Franc and Sauvignon Blanc. We know at last where Zinfandel originated – a small island off Croatia. We know that Syrah is the progeny of two much more obscure varieties from south east France, Dureza and Mondeuse Blanche.

But perhaps the biggest surprise of all was the discovery that a host of varieties associated with Burgundy and beyond – Chardonnay, Gamay, Aligoté, Auxerrois and Melon the Muscadet grape – are the progeny of the noble Pinot and a relatively obscure light-skinned grape Gouais Blanc which was widely grown in eastern France in the Middle Ages – and is also known as Heunisch is German-speaking countries and Belina Drobna in parts of eastern Europe.

It's not easy to find a wine made from this historic variety nowadays but vine geneticist José Vouillamoz (who once worked with Professor Carole Meredith at Davis but has now returned to his native Switzerland) put me in touch with the producer Josef-Marie Chanton of Visp in Switzerland's Valais. He makes a range of extremely pure, well-made, obscure local varietals of which one is Gwäss 2004 Vispertal, Gwäss being the local name for Gouais Blanc and Vispertal meaning that it comes from the Visp valley.

This elegantly packaged dry white is very aromatic – I smelt it as soon as it was poured, even some way away from my nose. There's surprising substance on the nose – something in the wood-to vegetal sylvan spectrum, although the wine is clearly unwooded. Very clean winemaking has resulted in something substantial (12 per cent alcohol) with real structure. There's very slight astringence but good balance. The acidity is refreshing without being tart and although the wine is relatively neutral, it's obviously from a fairly cool region.

This is a wine of historical significance but if it's strong flavour you're looking for, you could try Himbertscha 2004 Varen from the same producer which is chock full of fruit, or Lafnetscha 2004 Vispertal which has more of those green forestlike aromas reminiscent of the Gwäss.

The producer Josef-Marie Chanton has an excellent website at which explains all his unusual and modestly prices wares in German. Or you can contact him via the link below and discover that the Gwäss is just 18 Swiss francs, about £8 or $14, a bottle.

At about the same time as I tasted this white wine with such strong historic links to a famous, possibly dark-skinned grape variety (we do't know whether it was Pinot Noir, Pinot Blanc or Pinot Gris which was implicated with Gouais Blanc), I tasted another with extremely strong contemporary genetic links to another famous dark-skinned grape variety, from the New World this time.

Cygne Blanc 2005 Mount Benson has recently been launched as 'the Australian white Cabernet'. It is now grown on the Limestone Coast of South Australia having been propagated from a Cabernet Sauvignon vine grown domestically in Western Australia which apparently accidentally produced light-skinned grapes by Dorham Mann, son of the famous Jack (Houghtons White Burgundy creator et al) and his wife Sally. For financial reasons it was kept secret for 10 years until 1999 when they managed to register this new variety or mutation officially as Cygne Blanc (dunno why not plain old White Swan). In 2000 the Dorhams granted an exclusive licence to Port Robe Estate Vineyard at Mount Benson to grow this strange new beast and now there are almost enough sufficiently mature vines to produce wine in a commercial quantity.

So what's the wine like? Here are my tasting notes:

'14.5% Quite a definite gold. I'm afraid I got a very neutral nose – maybe the slightest suggestion of leafiness… Then lots of body and weight and more obvious blackcurrant fruit (the Cabernet influence?) on the palate plus some apple character. It's certainly not like Chardonnay but really just a full bodied alcoholic white wine at this stage. I can't really see why anyone would run to buy this wine. Slightly hot finish.'

There were just 12 sample bottles of the 2005 available for the UK and the wine will not be released properly outside Australia until the 2006 vintage, expected to retail for about £12 a bottle in the UK, is available. Perhaps as the vines age the wine will develop more character, or perhaps the story alone will be enough to sell the wine.

So there you have it, two white wines with stories old and new.