Originally published in Palate Press: The online wine magazine

By Erika Szymanski

Would you drink fluorescent green wine? Most molecular biologists-in-training experience their first taste of genetic engineering by transferring a jellyfish gene into (harmless) Escherichia coli, making the bacteria glow green under UV light. One slow day this past winter, my lab-mates and I contemplated the ramifications of transferring that same gene into Vitis vinifera. Fluorescent green wine? Fluorescent green wine! Oh, wait a minute. Do we seriously want such a thing? And has someone already done it?

Glowing grapevines are already a reality, though it is the leaf, not the grape, that glows, and the plants are a research tool, not a commercial endeavor. Unbeknownst to most of the wine-drinking world, GMO (genetically modified organism) wine—made with grapes grown from grapevines that have had non-native genes inserted into their genomes—is likely to be on shop shelves in the foreseeable future. This should not be much of a surprise, really. Most of the American corn and soybean crops are already genetically modified. In the US, food products containing GMOs need not even be labeled as such. The question is: will the uncommonly traditional and restrictive wine industry accept GMOs with the same aplomb as other food industries have?

Dr. Dennis Gray, a professor of developmental biology at the University of Florida and father of the glowing grapevine, speculates that industry and consumer acceptance may be the most difficult part of bringing genetically modified wine grapes to market. Dr. Gray and his research group have successfully modified—“transformed”—both wine and table grape varieties with genes that make them more resistant to problem fungi and pests. Expressing a specific gene from chardonnay in a Thompson Seedless variety, for example, dramatically improves its resistance to fungal diseases like powdery mildew or sour-bunch rot. The group has had success with a variety of Vitis species, including popular vinifera. The work is motivated in part by the goal of profitably growing grapes in Florida, an endeavor historically plagued by unmanageable Pierce’s Disease, but Dr. Gray sees benefits for growers of both wine and table grapes everywhere.

Gray’s group works with a technique called cisgenetic engineering, which means that they engineer grape plants with genes from grapes rather than, say, genes from corn or bacteria or jellyfish (save for those research-only green-glowing vines, that is.) Not only can specific genes be transplanted from one grape variety to another, expression levels can be boosted for genes that might ordinarily be active only part of the time or at low levels. In contrast to traditional breeding, this means that specific traits can be selected without impacting other desirable characteristics (in theory, at least), and the work can be done much faster than traditional breeding, too.

Powdery mildew on vines

Will the fact that only grape genes are being used make a difference to opponents of genetic modification? Maybe, but it is not likely to pacify everyone. Both the Australian wine industry and the California-based Wine Institute have issued public statements against the use of any genetically modified organisms, which would include Dr. Gray’s cisgenetic vines. Other researchers are also working on GMO grapes, and some have received clear indications that their work isn’t welcome. Just last August, members of an activist group called “The Voluntary Reapers” ravaged an experimental GMO vineyard in Colmar, France. The vineyard, capstone to a French National Institute for Agronomic Research (INRA) project to engineer grapevine fanleaf virus-resistant vines, was utterly destroyed. The same vineyard was attacked and damaged, to a lesser extent, in November of 2009. Genetic engineering experiments on grapevines by the INRA had been authorized for five years, ending in 2010, and it appears that the Institute has not pursued an extension.