By Roy Benaroch, M.D., Emory University
In the 1970s, technology was developed to more precisely modify an organism’s genetic code by splicing in new instructions from a different organism. Agricultural products made with this technology are what we now called GMOs, or “genetically modified organisms”. In popular media, some stories about GMOs are framed in worry and controversy. What’s the truth?
The Incomplete Story
Consumer Reports, a nonprofit better known for rating cars and dishwashers, wrote about GMOs in its 2014 article “Where GMOs Hide in Your Food”. They found that GMOs “lurk in many packaged foods”, including some that were labeled as not containing any GMOs at all.
But lacking in the Consumer Reports article was any sort of objective assessment of why GMOs should be labeled, or why, in fact, people ought to worry about their presence.
Indeed, the vague unease about GMOs that pervades stories like Consumer Reports’ led to this sarcastic headline from The Washington Post in 2016: “People Want GMO Foods Labeled—Which is Pretty Much All They Know About GMOs”. The Post article points out that while popular opinion supports the mandatory, specific labeling of GMO crops, that opinion seems to be resting on some incorrect facts.
This is a transcript from the video series The Skeptic’s Guide to Health, Medicine, and the Media. Watch it now, Wondrium.
More Marketing Than Science
Many people report in surveys that scientists have found GMOs to be harmful (that’s not the case), and that there’s controversy in the scientific community about the safety of GMOs. Again, that’s not the case—there’s a broad consensus in the scientific community that they’re safe, as reflected in a huge National Academy of Sciences report.
The Wall Street Journal has reported that the non-GMO label is more about marketing than science in the article, “Food Goes ‘GMO Free’ with Same Ingredients”. It points out some silly examples, like selling non-GMO salt, which is nonsensical. Salt is a mineral, not an organism, and has no genes to manipulate.
In fact, only eight GMO food crops are commonly available; of those, only two, papaya and squash, are commonly eaten by people directly. The rest, including corn, are much more commonly used as food crops for animals, or processed into food additives that contain no genetic material, like sugar.
Learn more about the importance of whole foods and fiber.
Are They GMOs At All?
There are other articles that poke fun at the anxiety over genetically modified crops. One, called “How Square Watermelons Get Their Shape and Other GMO Misperceptions”, appeared in The New York Times. It pointed out that ruby-colored oranges, white strawberries, and square watermelons are made without any GMO technology.
It’s sometimes hard to know, exactly, what should count as a GMO. The Times article discusses a new, non-browning mushroom developed with a completely new technology, not by inserting new DNA, but by clipping out a tiny portion of the mushroom’s native DNA. Should this be considered a GMO? So far, the US Department of Agriculture says it can be sold without additional oversight because no genetic material was added.
The question of whether something is or is not a GMO is likely to get even more complicated. We have heard about gene editing, about removing disease-causing genes from a human embryo. Similar technology could be applied to agriculture. The Wall Street Journal has also brought this up in their article, “Is This Tomato Engineered? Inside the Coming Battle Over Gene-Edited food”.
The Meaning of GMOs
“Traditional” GMO technology involves splicing in a gene from one organism into another. That’s not as unnatural as it sounds; microorganisms do this all the time, swapping genetic material, and almost all of the genes we carry are identical to genes carried by other organisms.
That’s right, a fish gene and a tomato gene and a human gene can all be the same string of instructions. In one example, a variety of rice was developed by inserting two genes from a daffodil and one from a bacterium that allows the rice to provide more vitamin A. This variety of so-called golden rice is still in development, but has the potential to address vitamin A deficiency in the developing world, preventing blindness, disability, and death.
Learn more about the controversies surrounding genetically modified plants.
Gene Editing and GMOs
But the newest technology, as reviewed in the Wall Street Journal article, involves editing the genome directly. There’s no other organism’s genes to insert, you just modify the genes that are already there.
If this receives the same regulatory approach as those gene-deleted, non-browning mushrooms, they won’t get the extra scrutiny required of gene-spliced GMOs. Now that we can edit genes directly, we could create genes within an organism that are carbon copies of a spliced gene, without the splicing.
Either splicing in genes or rewriting genes gets you to the same place: an organism with another organism’s gene. But almost all of our genes are already found in multiple other organisms.
Plants and Us
An NPR story, “You and Yeast Have More in Common Than You Think”, reviewed research confirming that human beings and common yeast—the stuff we use to bake bread—share thousands of identical genes, and it didn’t take genetic engineering to put them there.
The explosive growth of genetic knowledge and technology is breathtaking, and maybe sometimes a little creepy, too. Though we can easily map out our genetic information in fantastic detail, we don’t actually know, yet, what all of those details mean. We can now manipulate genes in human embryos and our food crops, and that’s making a lot of people uneasy.
Common Questions about the Confusion about GMOs
A GMO is a genetically modified organism, whose genetic code has been modified to improve it in some way. Nowadays, the term GMO refers to agricultural products whose genes have been modified in some way.
In what can be thought of as traditional GMO technology, the genes from one organism are spliced into the genes of another organism to improve the second organism in some way.
One example of a GMO is a type of rice called ‘golden rice’ which has one gene from a daffodil and one gene from a bacterium, which enables it to produce more Vitamin A.
