The influence of genetics in the development of anxiety.

Seven new genes linked to anxiety-type problems.

Research in the field of genetics has come a long way in recent times.

While our knowledge of genetics and how it works can still be greatly improved, the knowledge it provides has led to great advances. Science has made it possible to advance in the treatment of different diseases and disorders by locating the elements in DNA that cause or facilitate them and to identify those elements that cause or facilitate them. that cause or facilitate them and allowing the creation of more appropriate drugs and treatments to cure or alleviate their effects, or to avoid transmitting them to offspring.

An example of this is the treatment of various genetic disorders and the prevention of diseases with a high probability of occurrence (such as some cases of breast cancer). However, genetics does not allow an exact prediction of the occurrence of the phenomena, the expression of genes being affected by the life history of individuals. In the case of some disorders such as mental disorders, the exploration of the genome still has a long way to go, and there is still no exact knowledge of which genes predispose to suffer them, but it is known that in some cases there is a predisposition due to genetic influence. This is the case of anxiety disorders.

What is anxiety?

The concept of anxiety refers to a diffuse emotional state similar to fear, in which the advent of a future threat is expected. This fear is disproportionate, irrational and induces the avoidance or desire to avoid feared or fear-like situations.

The category of anxiety disorders includes various disorders such as generalized anxiety disorder, phobias and anxiety disorder with or without agoraphobia. In the past, obsessive-compulsive disorder was also considered as part of this category due to the fact that subjects with this disorder have a very high level of anxiety and their symptoms are derived from a particular management of anxiety, although its differential characteristics mean that it has been separated from this group in the latest version of the American classification of mental disorders par excellence (DSM-V).

Anxiety disorders are the most frequent type of mental disorder in both clinical and non-clinical populations. The presence of life traumas in early childhood is a risk factor for the development of anxiety disorders. Likewise, a certain genetic predisposition has been found in some subjects to suffer from it, a predisposition that has contributed to promote research into genes that may explain this relationship.This predisposition has contributed to promote research on genes that may explain this relationship.

Seven genes recently linked to anxiety

Recent research has attempted to find a link between some genes and the existence of anxiety disorders or anxiety-related symptomatology.

In this regard, it should be borne in mind that although we are talking about specific genes, the presence or absence of genetic predisposition does not depend on a single gene, but is considered to be polygenic. That is to say, a gene does not mark a characteristic by itself, but rather it depends on the joint action of various genes and how they are configured as a whole. and how they are configured in the chromosome set.

1. Mmp9 gene (Matrix metallopeptidase 9)

In this gene, four haplotypes or mutations and different combinations of specific alleles have been analyzed and found to be linked to anxiety. According to previous studies this gene is involved in coronary disorders and cancer, which correlates positively with both correlates positively with both anxiety as a predisposing factor and with anxiety as a as a predisposing element and to suffer from anxiety as a result of knowledge of the disease.

2. Bdnf gene (Brain-derived neurotrophic factor)

Only one haplotype of this gene, AGAT, shows a good high association with predisposition to anxious disorders.. This gene contributes to cell maintenance, allowing the modification of the synaptic space between neurons through the secretion of neurotrophins. It has also been associated with brain plasticity. It has been related to the neurotransmitter serotonin, it also affects the proliferation of neurons.

3. Ntf4 gene (Neurotrophin 4)

This gene is involved in the modulation of the synaptic space. It is essential for the survival and maintenance of neurons, being essential especially for those of the striatum. More research is needed regarding its involvement in anxiety disorders, but studies seem to indicate that it is implicated in the vulnerability to these disordersespecially if it occurs in conjunction with the previous one.

4. Genes Egr2 and Egr4 (Early-Growtg Response 2 & 4)

These genes are involved in synaptic plasticity, especially in learning and memory.. They are also involved in skull bone formation and myelination of the peripheral nervous system.

5. Grm2 gene (Glutamate receptor 2)

This gene participates, as can be imagined by its name, in the reception and metabolism of glutamate, the major exciter of the nervous system.the major excitatory of the central nervous system. This linkage to glutamate makes this gene an element strongly linked to anxiety disorders and even schizophrenia. In addition to anxiety disorders, it is linked to learning.

6. Arc gene (Activity-regulated cytoeskeleton-associated protein)

This gene is known and studied for its link with neuronal plasticity and the genesis of proteins that allow it.. It participates and acts on NMDA receptors.

Caution! Caution with Biological determinism

The discovery of these genes and their relationship with anxiety-related mental disorders is a major milestone in contributing to the study and treatment of anxiety disorders. However, it should be borne in mind that the presence of certain genetic configurations implies only an innate predisposition to express the phenotypes to the characteristics to which they predispose.

To consider that possessing these genes implies having an anxiety disorder would be a fallacy, since it could make us forget the shaping influence of the environment and education, elements that can awaken or ignore the biological predisposition.This is because it can make us forget the modeling influence of the environment and education, elements that can awaken or ignore the biological predisposition. Anxiety disorders, like other psychological disorders in general, have a plural and biopsychosocial etiology.

Care must be taken not to fall into reductionism and to consider the effect of all the variables that may have an implication in disorders, both anxiety disorders and other types of disorders.

Bibliographical references:

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