‘GMOs’ isn’t a four-letter word, but it is hard to define

After the decision in November that deemed genetically engineered salmon safe for eating — the first animal to garner such approval — the Food and Drug Administration is now treading regulatory water. On January 29, the FDA issued an import alert, essentially banning the sale of the salmon until the agency figures out how the fish should be labeled. I don’t envy its task.

Last fall, when I began reporting a story for Science News investigating many of the claims made about genetically modified organisms, I saw the labeling issue as pretty straightforward. I figured that knowing whether something contained GM ingredients would help consumers, including me, make more informed purchasing decisions. But the more reporting I did, the more I came to see “GMO” as a squishy descriptor with very limited use. Like the label “porn,” the definition of GMO often depends on “I know it when I see it” subjectivity.

Several states have been grappling with the GM labeling issue, and the results aren’t pretty. Legislation put forth in my home state of Vermont, for example, requires labeling only of GM-containing foods regulated by the FDA. As noted by Campbell Soup Company, which recently broke industry ranks and declared support for mandatory labeling of foods containing GMOs, Vermont’s approach is likely to lead to confusion for both food producers and consumers. Due to the hodgepodge nature of food regulation in the United States, the Vermont law would require labeling of Campbell’s original SpaghettiOs, but not SpaghettiOs with meatballs, because food from GM plants are under FDA regulation, but meat is the purview of the U.S. Department of Agriculture, not the FDA. (GM salmon is FDA territory because the inserted genetic material is considered a drug — go figure.)

Regulatory patchwork aside, a primary difficulty in defining GMO is it can legitimately be a super-broad category or an exceedingly narrow one, and either way renders the term meaningless. Many stabs at a definition, for example, are meant to distinguish “unnatural” products born from human tampering from something that occurs “naturally.” But much of the genetic modification that’s done by humans, nature it did first.

A routine method for “artificially” transferring DNA into a plant, for example, is by harnessing the powers of the microbe Agrobacterium. This soil bacterium (and some close relatives) is a natural genetic courier that has been inserting bits of DNA into plants since long before humans were around to worry about GMOs. Agrobacterium’s ability to genetically modify plants in the wild was first detected because the inserted DNA can cause crown-gall disease, an affliction of many (non-GM) crops.The microbe’s bioengineering prowess may have even played a role in domestication of the sweet potato: Last year, scientists reported that varieties of sweet potatoes gathered from across the globe naturally contain Agrobacterium-inserted genetic material that isn’t found in wild relatives. The discovery hints that the foreign DNA imparted some trait that made an ancient sweet potato ancestor more attractive to humans.

So perhaps we should define GMOs as organisms that humans have genetically modified. That definition opens an enormous can of worms; some would argue that “genetically modified by humans” begins with the dawn of agriculture. If you try and limit it to leave out traditional cross-breeding of plants — say, by defining GMOs as modified through nonsexual means — there’s still no bright line. Grafting,which occurs when plant tissues fuse due to mechanical pressure, is a long-standing practice in horticulture and it turns out that entire plant genomes can be swapped via grafted plants.

If you narrow the definition further to leave out ancient agricultural practices that most people are comfortable with, problems remain. Try this one: GMOs include modifications, done by people, that wouldn’t occur in nature. That designation leaves out many modifications that most of us consider indisputably GM, such as the gene-silencing techniques that yielded the recently approved non-browning apple and potato, or modifications made via the gene-editing CRISPR technology. These approaches don’t bestow new qualities by inserting foreign genes. Rather, they snip or dial down native genetic material, yielding traits might arise through time on their own via random genetic mutations.

Another difficulty with labeling is that it has the potential to cement false notions about the technology used to make GMOs in people’s minds. Many advocates of labeling, for example, feel strongly that they don’t want “biotechnology” to be used to produce food. Yet without this cursed biotechnology, we might still be collecting cheese-ripening enzymes from the stomachs of calves, for example, rather than using a more pure and arguably more humane version made by genetically engineered microbes (such microbes also make many of the vitamins and minor ingredients in our foods).

I understand the appeal of labels, and for many — myself included — labeling laws speak to an increasingly out-of-reach desire: that where we spend our money can make a statement about our beliefs. In conversations with friends, colleagues and sources about labeling laws, many point out that they aren’t worried about health effects or other red GM herrings —they just don’t want to support a food system based on industrial agriculture. That may be a valid desire, but it’s not necessarily achieved by labeling: Many plant biotech initiatives are not under the yoke of Big Ag. (Depending how you count, about 40 percent of agriculture biotech patents are held by industry giants, a hefty number to be sure, but certainly not enough to define the term.)

One way of avoiding the genetically engineered/modified labeling mess is to tell consumers to buy organic if they want to avoid GMOs; organic foods are prohibited from containing GM ingredients. But that option won’t help you avoid supporting an industrial food system: Many organic brands are now owned by titans of the processed food industry. And the organic label won’t rid the FDA of its genetically engineered salmon labeling problem: The U.S. has no organic standards for fish. So as the agency embarks on its efforts to finalize labeling guidelines, I say to them, good luck with that.