Transgenic Plants: Present and Future

When it comes to genomic editing, one thinks of the most modern techniques such as CRISPR, which recently won an prestigious award. It is considered almost science fiction or something futuristic. Genetic editing in animals and especially in people has ethical and moral implications that represent a very sensible barrier to what can be done. In fact, there is a strict regulation on the subject that controls all scientific production in this regard. However, it must be pointed out that the modified laboratory animals that are experimented on have saved countless lives to which all future ones will be added.

Then we have the plants, the great forgotten of the news and television networks. Plants have been genetically altered by humans since 1983. We are not talking about the traditional human selection that has been going on for millennia. But the selective modification of one or more genes with a specific and known purpose. Since we began to change them, they have not stopped contributing to human society. Agriculture is the basis of civilization. But not only that, the textile or pharmacological industry have also benefited from these advances too. Agriculture faces great challenges during the 21st century, desertification, pests, feeding a constantly growing population, avoiding deforestation, etc. For all this, transgenic plants can find a solution. Well, the scientists who work with them will find it.

Gene editing in plants is often believed to be limited, serving only to make them resistant to plagues and herbicides. This is because the "Bt" plants were the first event that was generated in plants. Bt plants carry one or more genes of the bacterium Bacillus thuringiensis that encode a toxin against herbivorous insects. Thanks to this event, many crops have been saved from plagues, since it is estimated that around 20% of agricultural production worldwide is lost due to diseases, parasites and predators (worth about 20,000 million dollars a year). To give the best examples: 362 million tons of soybeans are produced per year, of which 80% are transgenic Bt. Slightly more than 65% of the cotton that dresses the world and a third of the world production of corn are also Bt. And the competent and independent scientific authorities of governments or companies have not stopped repeating that these products are not worse than their non-improved counterparts.

The first transgenic plants emerged in the 1980s. Since then, crops have been improved in many ways other than resistance to pests. One of the most common, along with Bt, is resistance to the herbicide glyphosate. Soy, maize, canola, sugar beets, cotton and alfalfa  are the most common of them. In 2020 a new variety of sugar beet with a glyphosate resistance will be launched with a second event with which it is expected to improve production by 15% compared to current varieties. Both events, together with Bt, have a single purpose, to reduce the extension necessary to grow the same amount of food. But it has also been improved in other aspects, such as the flavor of strawberries. Thanks to the genomic study of the varieties that were traditionally crossed to create today's strawberries, an allele of a gene from wild white strawberries that had been lost by the traditional selection of strawberries based on their size and color has been recovered. Another of the best examples of genetic modification put at the service of society is found in arctic apples, where by silencing the polyphenol oxidase gene it has been achieved that a variety of apples and one of potatoes do not oxidize and last longer, reducing food waste.

Finally, we cannot fail to mention the golden rice. Rice is the main source of food in the world and in many regions an almost exclusive source. However, rice contains low levels of vitamin A. During development, a lack of vitamin A causes blindness and death. In golden rice, 3 genes have been modified so that the grains do not degrade their own beta-carotene, a precursor of Vitamin A. It is estimated that it could save the lives of about 1 million children a year.

All these genetically modified organisms (GMO) have been carried out by conventional techniques. The appearance of CRISPR will revolutionize the landscape in a fundamental technical and practical aspect. Previously, events were stochastically introduced to the plant. This involved the problem that the insert sometimes fell into a relatively large site and could alter the internal genetic rhythms of the cell. Obviously these plants were discarded but time and money was lost in the process. Thanks to CRISPR and targeted editing this will be avoided. Not only will we avoid important areas but we will be able to better order the modification events and make them work more efficiently with the cell's own machinery.

The GMO controversy is on the street, not in the labs. The scientific community has continuously demonstrated food safety and the potential that these products generate. However, the political measures are lukewarm to say the least. The European Union has one of the most restrictive regulations on the planting of GMOs. On the legal side, the EU considers plants modified by CRISPR to be considered GMO and regulated in the same way. Spain and Portugal are the countries that grow the most in Europe, although worldwide they are around 20th position in quantity produced. However, the EU has no problem buying modified products, since its competent body published several studies demonstrating the safety of modifications at the food level.

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