The role of GMOs in Napa Valley wine production raises concerns

The increasing, unadvertised research and development of GMO in Napa winemaking is starting to ring alarm bells. In three Napa Valley Register articles published last week, journalist Juliane Poirier Locke points to the genetically modified yeasts and genetically engineered grapevines that are being developed at UC Davis, Cornell, and other universities around the country—or insinuating themselves into the winemaking industry in California and elsewhere.

The manipulation of grapevines is not a new concept. Ever since the phylloxera epidemic of the late 1800s, when most of the vineyards in Europe were destroyed, winemakers worked to hybridize or develop resistant rootstocks to make the vines stronger and disease-resistant. But today’s engineering is much more high-tech: Geneticists are using genes from pears, peas, herb amaranth, synthetic material, and even African clawed frogs to create disease-resistant grapevines.

Although genetically engineered vines and fruit are still in the R&D phase, genetically modified yeasts have hit the market. The use of added yeasts isn’t novel—most wines are now made with a wide range of commercial yeasts. But two new yeasts on the market—ML01 and ECMo01—haven’t just been cross-bred, they’ve been genetically engineered to prompt speedier fermentation and reduce urethane, a suspected carcinogen.

While no local winemakers have admitted to using these yeasts, they’re not required to, and in a consumer climate so GMO-wary, who would? Locke, however, cites a 2006 Sacramento Bee article in which a distributor of yeasts is quoted stating that some GMO-yeast wines from California are already on the market.

Napa Valley, where Locke’s articles were researched, has a few outspoken anti-GMO advocates who are meeting regularly to monitor the issue. PINA, or Preserving the Integrity of Napa’s Agriculture, and the Napa GMO Stakeholder Group, are lobbying to pass the same kinds of bans on GMOs that Mendocino and Santa Cruz County have effectuated (a GMO ban in Sonoma County was rejected in 2005).

Many people believe we can solve our pest problems without the use of GMOs. “The history of agriculture shows us that there will always be another pest,” said Miguel Altieri, a professor of agroecology at UC Berkeley. “Will we have to keep re-engineering the vines for each one? The solution is not in genetic re-engineering but in making our agricultural systems more resilient.” He believes in a more diverse vineyard, in which insects have food choices other than the grapevine.

Battles like these are being fought in every sector of the industry, from wine to vegetables to cheesemaking. Which side of the lobby will prevail?

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The ECMo yeast isn't a GMO. I don't like GMOs, but I also think we have to be accurate when notifiying the public about them. If you perpetuate the original bad reporting, it just discredits our cause.

ECMo01 most certainly was created through genetic engineering. The developer took genes from various yeast strains and artificially inserted them into a traditional wine yeast strain. As explained in one of the articles, it's this act of inserting genes into an organism that can create unpredictable effects, making safety testing, which the developer didn't do, necessary.

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