What is CRISPR and why is this biotechnology bringing the future closer

A lot of interesting technologies have appeared in the last decade. But CRISPR, according to many experts, is one of the most promising. At the same time, few people understand what the essence of gene editing is. To popularly explain how it works, VOX has published a short manual "for dummies".

The full name of this technology looks like CRISPR/Cas9. It is a powerful genome editing tool based on the protective mechanism of bacteria. Biologists were able to put him at the service of science and learned to change the DNA of plants, animals and even humans with his help.

We think that such changes require months or at least weeks of work. But CRISPR shows excellent results after a few days. This is the first effective and accurate tool for working with the genome in the history of mankind.

The first unusual feature of microorganisms was noticed in 1987 by scientists from Japan. They examined Escherichia coli - E. coli and noticed an unusual sequence in its DNA. It was not possible to find out what it is needed for, but soon such repetitions were found in the structure of other organisms.

It is clear that the discovery, which had not yet been used, received a tricky scientific name: CRISPR - short palindromic repeats, regularly arranged in groups (Clustered Regular Interspaced Short Palindromic Repeats). Until 2007, CRISPR could not be used. But then microbiologists studying the Streptococcus bacterium were able to determine that it was part of the bacterium's immune system.

Bacteria also have dangerous enemies - viruses. They must repel their attacks and special enzymes are produced for this. After each victory over the virus, the bacterium retains part of its genetic material inside the CRISPR sequences. In the next virus attack, this element is used for protection.

In the event of an attack, the bacterium produces Cas9 proteins with fragments of the virus' genetic material. If this section coincides with the DNA section of the virus, then Cas9 cuts the genetic material of the latter and neutralizes the threat. It seems that this phenomenal discovery is interesting only to microbiologists.

That was until biologists Jennifer Doudna and Emmanuel Charpentier started studying CRISPR in 2011. They found out that the protective protein can be outwitted and put artificial RNA in it. A protein with such RNA will look for similar fragments. Having found a similar piece of DNA, regardless of whether it belongs to a bacterium or a virus, the Cas9 protein begins to grind it. Dudna and Sherpantier were convinced that this method helps to cut any genome in the right place.

Again, the joy of biologists is not too clear to us. But they immediately realized that this was the real discovery of the century. Immediately after the discovery, 100 works about CRISPR were published in the world, and in just 6 years there were more than 14 thousand of them. All areas of application of the technology are innumerable. For example, it can be used to determine what functions a particular section of DNA carries. It is enough to cut it out with CRISPR and find out what function the microorganism has lost.

But DNA disassembly is interesting only to microbiologists, and the rest of the world wants to know about the practical application of the discovery. And it turns out there are a lot of such applications. First of all, CRISPR is interesting for agriculture. With the help of technology, it is possible to make crops even more nutritious, juicy and resistant to diseases, weather factors and stress.

You can go even further, for example, cut out the gene responsible for allergies from peanuts. It is not difficult to rid bananas of a predisposition to a fungus that destroys thousands of hectares of plantations.  You can also use CRISPR in animal husbandry, for example, by editing the genome of a cow.

There is also a huge potential for genome editing in the field of medicine. The possibility of using it in medicine is already being studied. Mutations that cause serious diseases can be cut out of the human genome. CRISPR can be used to fight sickle cell anemia. Huntington's chorea genes or BRCA-1 and 2 mutations associated with breast cancer can also be removed. Theoretically, this method is also suitable for the treatment of HIV.

But it is too early to talk about the imminent appearance of new methods of therapy. So far, Cas9 fragments do not differ in accuracy. They can cut out the wrong part of the DNA and it is dangerous for health and life. Research in this direction continues and doctors are getting closer and closer to the cherished goal.

But the creation of antibiotics and antiviral drugs with CRISPR is more realistic. It's no secret that bacteria adapt quickly to antibiotics and therefore new drugs are constantly being created. It is expensive and not always effective. CRISPR can destroy bacteria, regardless of their resistance to antibiotics.

And genome editing can also be used for so-called "genetic drive". This means changing the genome of an entire species. A living organism transmits half of its genes to its offspring. With the help of editing, you can achieve 100 percent of the transfer.

Thus, an important feature will spread twice as quickly through the population. As an example, the fight against mosquitoes can be cited. Geneticists influence their DNA so that only females or males will be born. Of course, this will lead to a rapid extinction of the species. Of course, it would be a disaster, but as an example it looks good.

But the most coveted and at the same time controversial way to use CRISPR is to work with the human genome. Technology makes it possible to receive children with the specified qualities. This is very difficult and still belongs to the realm of fiction. But on the other hand, what we see around us, even some 20-30 years ago, it also seemed impossible.

To learn how to create "designer babies", you need to master working with thousands of different genes. There is no doubt that scientists will have such knowledge in the future. It's just a matter of scientific progress and time.