The Origin Of Fear Is In A Corner Of The DNA

start the fear from brain This is one of the great challenges facing neuroscientists. Phobias or post-traumatic stress disorder They can deal a serious blow to the normal development of the life of those who suffer from them. Therefore, finding the neural mechanisms they are associated with is vital. Now, a team of scientists from various Chinese and Australian research centers have found a possible key in the mouse genetic material.

These are sequences of what is called unwanted DNA. In other words, genetic material that does not translate into protein. But just because you don’t experience this translation doesn’t mean it’s useless. In fact, in this case, it seems that it behaves like a kind of bridge, which allows the expression of other genes associated with the extinction of fear.

It is important to emphasize again that the study was carried out in mice. This means that we don’t yet know if it could be extrapolated to humans. However, these scientists, whose work was recently published in Cell reports, remember that many fundamental molecules involved in this type of process are conserved in all species, so it is not something that can be ruled out. We should study more, but at least they already have a thread to pull in the face of development future of treatments against post-traumatic stress syndrome or phobias. Let’s see what this thread is all about.

Post-traumatic stress: when fear settles in your brain

the post-traumatic stress occurs when a painful memory it remains fixed in the hippocampus of the brain and it is practically impossible to erase it.

The person who suffers from it continually relives all the pain it has caused him, to the point that on many occasions his life becomes a nightmare. the phobias they are not so much related to mind, but they are also related to fear. Specifically with an irrational fear of something that is generally harmless. Although both can be treated with psychological therapy or even some virtual reality programs, if the situation is serious, especially when it is related to post-traumatic stress, it is much more complicated.

Studies are underway with a combination of hallucinogenic drugs and psychological therapy to combat post-traumatic stress

Some very promising treatments are beginning to be studied, such as the one that combines psychological therapy with the administration of hallucinogenic drugs. And it is that we have seen that the substance in question can to open the door brain for a few moments, so that through therapy you can remove the fear or painful memory and enter a new one.

But all this is nothing more than studies that are in very preliminary stages of research. A key to completely turning off fear in the brain has yet to be found. That’s why this new study is so interesting.

Nogas1974 (Wikimedia)

Not everything is protein

Our DNA is ours instruction manual. It contains all the commands necessary for the proper functioning of our body. But they cannot be read directly.

In order to interpret what these instructions say, it is necessary to transcribe DNA into RNA and then translate it into protein. Proteins will be the ones that will ultimately be involved in all these processes necessary for our proper functioning. All our cells contain the same DNA. However, not all instructions are read at all times and in every cell.

Although all our cells have the same DNA, not everything is expressed in the same way

For example, a gene with the code to make insulin will not be read in the cells of the eye, but it will be read in those of the pancreas. That’s what we call gene expression. This gene for insulin synthesis is found in all cells, but it is expressed only in those of the pancreas and only when necessary. Therefore, it is only in these specific cases that DNA is transcribed into RNA to continue the whole process.

Now, not all DNA eventually becomes protein. It can be transcribed into RNA, but not go to the next step. That’s what we call unwanted DNA. A rather unfair term, considering that it can have very useful functions. It is what happens with these sequences associated with the extinction of fear that could make it possible to develop treatments against phobias or post-traumatic stress syndrome.

The solution was in the ‘trash can’

Although there are still many unknown data about fear, at least scientists have already been able to find its location in the brain, more precisely in the sublimbic prefrontal cortex.

In addition, its extinction, so necessary to treat post-traumatic stress disorder and phobias, has been seen to be linked to epigenetics. It is a branch of genetics that studies DNA modifications that affect its expression, but not its sequence. That is, the instruction manual remains the same, but a few changes are made to the instructions that are read every place and every time. However, the definitive method for extinguishing fear has not yet been found. through epigenetics.

Epigenetics is the branch of genetics that studies changes in gene expression without altering the DNA sequence.

Knowing this, the authors of this study focused on RNA, specifically what is called long non-coding RNA. These are RNA sequences longer than 200 nucleotides (the blocks that contain it), which are not translated into proteins. Previous studies carried out with this type of DNA have shown that 40% of what has been identified so far is concentrated mainly in neurons. But, even more precisely, there is a type of this RNA, called eRNA, found in the infralimbic prefrontal cortex of mice. there where it lives the fear.

Investigating this line, they found a gene called ADRAM which does not encode any proteins, but it serves as a scaffold for other molecules to access a gene for expression. In addition, it coordinates other molecules, including eRNAs, which express a gene that helps reduce fear.

Knowing this, they took genetically modified mice to silence this gene. The objective was to see if they experienced a difference compared to others when they underwent a session of Conditioned fear and its subsequent deconditioning. And so it was, because after the process they were still afraid, as if the deconditioning hadn’t worked. But, interestingly, the rest of the fear and anxiety behaviors remained unchanged.

Therefore, it could be that so far all these studies aimed at turning off fear by turning off anxiety processes have not been on the right track. They may be different processes and that is why it is so difficult turn off those feelings. We should also see if other cognitive processes are altered by modifying this gene. It will be necessary to continue to study this line and especially to check if it can be extrapolated to humans. Plus, it’s only been studied in male mice, so we’d have to see if females experience the same effect. There is a long way to go; but, for now, we can say that, on this basis, the keys to ending phobias and post-traumatic stress were hidden in the garbage.