GMOs used in agriculture are probably the technology most unfairly hated by Europeans. While it represents even less risk than nuclear energy, it is even more rejected, to such an extent that its use is almost abandoned in Europe. However, as progress goes on, this technology brings even more benefits.
We are going to focus here mainly on genetically modified crops (and a little on animals), because it is the most important subject in terms of public debate, even if in fact the term “GMO”, strictly speaking, also designates genetically modified bacteria and yeasts which are of little interest to the general public.
Plant breeding: a thousand-year-old practice
One of the reasons why GMOs are so scary is that we think that we have suddenly discovered a new technology that allows us to radically modify plants, something that we would not have done so far, and which would therefore represent a new risk. In addition, we would now take ourselves for God by trying to modify plant species.
But in reality, changing plants from their natural form is something that humans have been doing for thousands of years. For example, “classic” cabbage, broccoli, cauliflower and Brussels sprouts are originally one and the same plant: wild cabbage. It is the selection and crosses made by humans which have made it possible to obtain all these very different varieties. Carrots were originally white, yellow or purple, and their orange color today is the result of human-made crossbreeding and selections, as is their sweet taste. Maize, on the other hand, originally had tiny ears no bigger than those of wheat [2].
These examples illustrate the general case of crops used in agriculture. You wouldn’t probably recognize their wild ancestors if you saw them. Plants that are used in their original form are rare but still exist, such as blueberries or wild strawberries for example.
It is a very good thing that man has improved plants, because originally edible plants were scarce and provided small amounts of food. The plants used in agriculture are therefore a huge technological heritage thanks to the work of generations of farmers.
These improvements were achieved mainly thanks to two techniques:
Selection: Between the descendants of a plant, there are some random variations from one individual to another. If we choose for reproduction the offspring that have most of the desired characteristics, we will make these characteristics more frequent in the following generation. This mechanism has been understood for a long time by man, long before understanding that he was imitating the natural phenomenon of evolution by natural selection. Today, we understand that by doing this, we are in fact shuffling thousands of genes in a random manner.
Crossing: If we have two varieties of a plant, each with advantages and disadvantages, we can cross them to combine the advantages (we proceed by trial and error since we can just as well get all the disadvantages).
It is thanks to these two techniques that man has radically modified plant species to create the majority of varieties used today in agriculture.
This also applies to farm animals, which are also very different from their wild ancestors, although the differences are less dramatic than for plants.
New genetic technologies
What is a GMO?
What characterizes a GMO is therefore not the goal of modifying the genome of an organism as such, but the method used to achieve it. Instead of using selection and crossing, which mix up millions of genes at the same time, we take a specific gene and insert it into the organism we want to improve. It is therefore a “precision” technology allowing us to choose the gene of interest by transferring it from one living being to another. Scientists call this operation a transgenesis.
A particularly interesting aspect is that we can take a gene from a species which cannot normally interbreed with the species we want to modify. For example, the GloFish company inserted a jellyfish gene into fish to make it fluorescent.
Note that gene transfers also sometimes occur in nature, and is for instance the at the origin of the "Renan" wheat variety used in organic farming in Europe (which is not considered a GMO because the transgenesis has occurred without human action) [9].
Once the transgenesis has been carried out, there is no longer any need to make new genetic operations, because we simply use the descendants of the modified specimens. For example, if you buy GMO maize seeds or GloFish fish, these seeds and fish have not undergone any genetic operation themselves, they are simply the remote descendants of individuals who were originally genetically modified.
GMOs are not just about plants and animals. In fact, genetically modified bacteria and yeast are widely used without attracting the wrath of anti-GMO activists, for example to create vaccines. We also make a colossal quantity of genetically modified “laboratory” animals (mice, rats, etc.) to study diseases or the inner workings of organisms, but these GM animals are not intended to leave laboratories.
Other innovations
What the public and the law designate as genetically modified plants are those for which at least one gene has been inserted by transgenesis. But transgenesis is not the only modern genetic technique that can be used to improve a species. One can also use:
Mutagenesis: the plant is subjected to radiation or mutagenic chemicals, which strongly increase the mutation rate compared to natural evolution. The plants which “luckily” obtained the desired modification are then kept. Plants varieties created with this technique are not considered as GMOs by European regulations [2].
Directed mutagenesis: It's just as the previous technique, but it induces mutations only on a specific gene instead of affecting all genes of the plant randomly. A plant variety created with this technique is considered as a GMO in Europe but not in America [2].
What is special about these techniques is that they allow us to obtain a plant that could very well have been obtained with traditional techniques of selection/crossing, since we do not insert a gene from another species. The method used is therefore a “modern” genetic technology, as for GMOs, but the result is indistinguishable from what could have been obtained with traditional methods (although in much less time).
All this shows that the GMO/non-GMO distinction is more like a legal notion subject to debate rather than a clear scientific distinction.
What are transgenic plants used for?
Transgenesis is just a technique and the effect depends on the gene you insert into the plant. Here are some examples of genetic modifications used:
Herbicide tolerance: the genetically modified plant is resistant to a herbicide, which still kills all other plants. The farmer can then easily apply this herbicide to his field to keep only the plants he wants to grow.
Insect resistance: the plant produces an insecticide protein which kills an insect that would otherwise harm the plant. The goal here is to avoid using an insecticide that would otherwise have to be spread on the whole field (which would bring its own risks and environmental impacts).
Chemical composition: BASF's Amflora potato has a modified chemical composition which makes it more suitable for industrial processes.
Aesthetics: carnations genetically modified to be purple [10] and the GloFish fluorescent fish mentioned above.
Nutrition: Golden rice includes extra vitamin A (and also has a golden color) to help fight vitamin A deficiency in developing countries.
A plant can be genetically modified several times (ie. several genes are inserted) to have several desired characteristics. In the World, 45% of the surface of GM crops have both a herbicide tolerance gene and an insect resistance gene [1].
Are GMOs dangerous?
The currently cultivated GM crops are not dangerous for health, whether you eat them directly or whether you eat the meat of animals which have consumed them [8].
But we must keep in mind that it does not make sense to speak of the danger of GMOs “in general”, in the same way that it would not make sense to talk about the dangerousness of plants in general. Even if a genetically modified plant was found to be dangerous, that would not imply that all GMOs are dangerous. This would reveal a risk with the specific gene inserted, and call into question all varieties with the same inserted gene, but this would not imply any risk for GMOs made by inserting other genes.
The good question is: is the gene you insert dangerous? It can be completely different from one gene to another. But both in Europe or the United States, studies are being conducted to verify the safety of genetically modified varieties and they have so far found nothing to worry about.
The paradox is that this technology is rejected even more in Europe than nuclear power, although it has never killed anyone, unlike nuclear power. GMOs have been used on a large scale in agriculture for over 20 years [6] without causing any known damage to health.
GM crops in the world
A complete failure in Europe
In Europe, GMO regulations are very heavy and only two GM crops are allowed to be cultivated: the Amflora potato and the insect-resistant maize MON810. Only MON810 maize is still grown in Spain and Portugal.
However, the European Union imports a significant amount of genetically modified plants for animal feed, mainly from the United States. This is because many genetically modified plants are allowed to be imported once harvested, although they are not allowed to be cultivated in the EU.
In addition to very stringent EU regulations, individual countries have sometimes added their own bans against the rare crops allowed by the EU. For example, France has tried on several occasions to illegally ban MON810 in violation of European law [3] [4].
But in addition to heavy EU regulations, country-imposed bans and a population fearful of GMOs, crops are often illegally destroyed by anti-GMO activists. Even research carried out by public institutions is not immune to this phenomenon [5].
All these issues have led industry and public research organizations to completely abandon research on genetically modified plants in Europe.
Massive development elsewhere
If this technology is shunned by Europeans, it is nevertheless massively adopted in other countries. In fact, 5 countries alone account for 91% of the area cultivated with genetically modified plants: the United States, Brazil, Argentina, Canada and India.
The most widely cultivated genetically modified plants are soybeans, cotton, corn and canola. In the World, the majority of soybeans and cotton produced are genetically modified, with 78% for soybeans and 76% for cotton, compared to 30% for maize and 29% for canola (source [6] p. 74).
Since 1996, the area planted with GMOs has increased by around 10 million hectares each year, but the increase has been slower since around 2012, with only 3 million more hectares planted each year [1] [6]. This is partly due to the fact that in the 5 major adopting countries, we are reaching “saturation". For example, in the United States, we already have more than 90% of soybeans, cotton, corn and rapeseed that are GMO varieties. So we can no longer increase GM crop surface ratio. On the other hand, new genetic modifications are added to GM crops, which means that varieties “modified once” give way to varieties “modified twice".
What about GM animals?
Unlike genetically modified plants which are used extensively in agriculture, the use of genetically modified animals is much rarer. GloFish fluorescent fish are of course an example and have been on the market since 2003, but they are aquarium fish produced on a small scale.
The first genetically modified animal allowed for human consumption is the AquAdvantage salmon. This is an Atlantic salmon modified to replace its growth hormone with that of another breed of salmon to allow it to grow all year round and not just during spring and summer [7]. The first country to approve this salmon for food was Canada in 2016, followed by the US in 2019.
Conclusion
Genetically modified crops have been used on a large scale for more than 20 years in many countries without causing any health issues. That is why I think it’s a pity that European citizens are so afraid of it. Genetic modification is a new tool which opens up new possibilities compared to traditional selection, and it can bring many benefits: increase in yields, decrease in pesticides used, adaptation to climate change, resistance to diseases, increase in nutritional quality or taste. The more technology progresses, the more new genetic modifications are invented and the more they bring benefits.
What I think could possibly present a real issue would be the genetic modification of animals, because this could have negative consequences for their welfare. Of course, this needs to be a case-by-case assessment, since a genetic modification can either be good or bad for animal welfare. However, this is still a minor issue for the moment, as the AquAdvantage salmon is the only genetically modified animal on the market.
Sources
[2] GMOs: a legal category with debated contours (in French)
[4] What lessons can be drawn from "the MON810 case” ? (in French)
[5] The destruction of INRA's GMO vines (in French)
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