What are GMOs?
From the book by Andrey Sokolov and Tatiana Sokolova "The world and humans for students and their parents".
What are GMO?
What will do we eat instead of meat? Really GMOs?
GMO is a genetically modified organism. Many people think that GMOs have appeared quite recently. But this is not the case.
The easiest way to say that genetically modified organisms have always been. They appeared at the moment when life appeared on Earth and information began to be inherited through DNA and RNA.
What are GMOs?
Let's figure it out. In detail and from the very beginning.
When life was born and it became necessary to transmit information about flagella, horns, tails and hooves to the next generations, special molecules appeared in which this information is stored and with the help of which this information is converted into building material - proteins and cells. These special molecules are called DNA and RNA.
In all organisms, except for some viruses, information is stored in DNA and is converted into proteins using RNA.
It is the changes in DNA that are the modification of genes, it is as a result of such changes that GMOs are obtained.
And the fact is that changes in DNA are a normal evolutionary process. It is thanks to such changes that multicellular organisms appeared from unicellular organisms. From multicellular organisms - fishes and seaweed. From fishes - amphibians. From seaweed - plants. From amphibians, over hundreds of millions of years of evolution, are birds and mammals. From mammals - we humans.
If new GMOs did not appear, then we would not exist.
The trick here is that despite all the diversity of animals and plants, it is based on only four small molecules - nucleotides: guanine, cytosine, thymine and adenine. And these molecules, both in humans and in tomatoes, are the same.
Like LEGO bricks.
DNA can be thought of as a long chain of LEGO cubes of equal size. Where adenine is a red cube, thymine is blue, guanine is yellow, cytosine is green.
Only 4 cubes create the opportunity for a huge variety of life to exist. Create a whole palette of colors, proteins, lives.
Does it seem impossible? But after all, all the films that we download on torrents, all the TV shows, all the musical compositions in our MP3 players, all the voices of relatives and friends in cell phones, all e-books, everything that is in our computers, all the electronic systems that control airplanes and satellites, all photographs in our cameras are just two cubes. Cube 0 and Cube 1. Black and white. Change the sequence of these cubes, and the photo of a distant galaxy captured by the Hubble telescope will turn into your grandmother's voice on your phone.
It is the same in nature. But not two, but four cubes are used to transfer information, which allows you to create such a variety of life that no computer with a binary code can yet do.
How does information become a product?
In order to create a protein, and then a cell, and then a living organism (chicken, apple or human), proteins are synthesized in each cell based on information obtained from four DNA cubes. There are many proteins. But they all consist only of individual LEGO cubes - amino acids. These are slightly different cubes. Let's call them LEGO 2.0.
There are 20 of these amino acid cubes. These 20 cubes, making up unique chains, create proteins that make up our body, and which we eat every day at breakfast, lunch and dinner.
What are we eating?
It seems to us that we are eating corn, chicken, beef, bananas or potatoes, but in fact, we are eating molecules.
We eat nucleotides: adenine, cytosine, thymine and guanine (and uracil is also a nucleotide from RNA that replaces adenine when reading information).
We eat 20 amino acids: glycine, alanine, valine, isoleucine, leucine, proline, serine, threonine, cysteine, methionine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, arginine, histidine, phenylalanine, tyrosine and tryptophan.
We also eat various carbohydrates, fats and much more. But this has nothing to do with GMOs, since fats, carbohydrates and other compounds are not encoded in DNA, and therefore cannot be changed at the genetic level, at the DNA level, at the level where nature, breeder or geneticist creates a new GMO.
Why is it important to understand what we eat?
For one simple reason. The nucleotides and amino acids that we eat from genetically modified corn are exactly the same as the nucleotides and amino acids that our great-great-great-ancestors ate, harvesting this corn not even in our fields, but in the wild.
The fact is that everything that enters our stomach is immediately exposed to enzymes that grind all cells and food molecules to a state in which it is convenient for the body to absorb them in the intestines. Further, this food travels through the body with the blood stream in the form of nutrients: nucleotides, amino acids, glucose and other minimally complex molecules. Neither corn nor chicken legs travel through human blood vessels. And molecules travel, completely identical to those of which the human body itself consists.
Thymine from maize is indistinguishable from human DNA thymine; lysine from pork is indistinguishable from human protein lysine. And it will never be different, even if geneticists develop a new GMO - a hairy and horned pig that gives milk and is the size of an elephant. Adenine and the other three nucleotides, lysine and the remaining 19 amino acids in this pig will remain the same and identical to human or corn. Only the sequence of how these nucleotides are located in DNA and amino acids in proteins will change.
But we don't eat proteins or DNA. These are too large structures to pass from the intestines to the bloodstream. We only eat amino acids and nucleotides. And they are still the same as millions of years ago.
How long has a person started creating GMOs?
In terms of evolution, of course, not so long ago. Long before man, nature experimented with the creation of GMO reptiles - dinosaurs, with GMO dinosaurs - birds. With GMO animals - dolphins and whales. Or rather, nature was only engaged in creating new GMOs. But she did it not on purpose, not aiming, and therefore for a long time and with a lot of mistakes and extinct animal species.
Try to close your eyes yourself and without any thought or purpose move the pencil over the paper. How soon will you draw a bear using this technique? So it took nature billions of years.
For the time being, as long as people liked to hunt and collect, the pace of creation of GMOs through evolution suited people.
But as soon as a person began to sow grain, grow fruits and vegetables, graze livestock, he immediately invented his own proto-genetic engineering, which he called selection much later.
What is "selection"?
As soon as a human began to plant, sow and graze, he began to take away: the grains are larger, the fruits are sweeter, the pigs are thicker and the goats are milder and not buttery. As a result, there were breeds and varieties that we plant in fields, orchards and vegetable gardens, grow on farms and pastures and buy in boxes and bags in stores.
All this, from the point of view of genetics, is just GMO. Humanity has long been eating all sorts of GMOs. From the time of Mesopotamia and several millennia earlier.
Selecting larger grains, a person selected those plant specimens in whose genes changes (mutations) occurred. These changes led to the formation of new proteins that allowed the grains to grow larger.
Nature, evolution, such selection was useless. But the person who was thinking about a delicious cake - really needed it.
Changes in genes that lead to changes in proteins and the emergence of new qualities of living organisms occur constantly. Sometimes due to an error that occurs during cell division, sometimes due to an accident that occurs in the same process, sometimes due to external influences of the environment, for example, radiation, which falls on the Earth for as many years as our Sun and the Universe have existed.
Nature let the selection of species and varieties take their course - whoever survives will survive. A person, starting from ancient times and ending with the last century, did not allow amateur performances and selected only those copies that were useful to him. The result is plants that cannot survive in the wild without human care, but that make up the entire human diet with the exception of wild grasses and berries. Animals have appeared that cannot survive without humans, cannot escape and defend themselves from predators. Animals that can produce a lot of meat, wool and milk, but cannot escape from predators without the help of a shepherd with a gun.
How is GMO and genetic engineering different from breeding?
From the point of view of the buyer in the store - nothing. Genetic engineering creates GMO products in the same way as breeding, only much faster and more targeted. A geneticist does not wait for the trait that a person needs to appear in a fruit or vegetable as a result of a random mutation. This can take tens or even hundreds of years. This may never happen at all.
Therefore, the geneticist decides what trait he wants to get and looks for a sequence of nucleotides that can create the desired protein, which ultimately will lead to the appearance of the desired trait, which will be passed on from generation to generation.
For example, pest resistance. Either a faster ripening, or increased production of carbohydrates, which will make the product sweeter. Or a rapid build-up of muscle mass, which will lead to a decrease in the cost of cutlets.
In order to do this quickly, accurately and efficiently, genetic engineers have many clever ways, which, however, in the end consist only in the fact that they change the sequence of four LEGO cubes in DNA, which leads to a change in the sequence of 20 cubes LEGO 2.0 in the proteins of a genetically modified organism, fruit, vegetable, grain, milk, egg or meat in our plate.
Can you eat GMOs?
No matter what genetics do, no matter what new GMO they create, when we go to the store and buy a product containing this GMO, all the same 4 nucleotides and 20 amino acids enter the blood of ours.
All the same 4 nucleotides and 20 amino acids that entered bloodstream and cells the ancestors of hunters and gatherers long before the advent of agriculture, breeding and genetic engineering.
And how will GMO replace meat?
It would be more correct to say it will not replace, but has already replaced. And it is quite possible that by the time you read this book, fake meat burgers will be on sale in your nearest supermarket.
Scientists have learned how to grow artificial meat in a test tube, which consists of the same muscle fibers, nucleotides and amino acids as the meat of a killed animal. But you don't need to kill anyone in this case. After all, everyone has the right to life.