The influence of genetics on the development of anxiety

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

Although our knowledge of genetics and how it works can still be greatly improved, the knowledge it provides has enabled great advances. Science has made it possible to advance the treatment of various diseases and disorders by localizing the elements of DNA. that cause or facilitate them and allow the creation of drugs and more appropriate treatments to cure or attenuate their effects, or to avoid passing them on to the offspring.

An example 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 do not allow an accurate prediction of the occurrence of phenomena affecting the expression of genes through the history of human life. In the case of certain disorders such as mental disorders, genome exploration still has a long way to go, as it is not yet clear what genes predispose them to suffer, but it is known that in some cases there are predisposition to genetic influence. This is the case with anxiety disorders.

What is anxiety?

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

The category of anxiety disorders includes various disorders, such as generalized anxiety disorder, phobias, and anxiety disorder with or without agoraphobia. Obsessive-compulsive disorder was formerly also considered to be in this category because subjects with this disorder have a very high level of anxiety and their symptoms are derived from a particular management of it, although its characteristics Differentials mean that it was separated from that group in the latest version of the American Classification of Mental Disorders Par excellence (DSM-V).

Anxiety disorders are the most common type of mental disorder in clinical and non-clinical populations. The presence of life-threatening trauma in early childhood is a risk factor for their suffering. Likewise, some genetic predisposition has been found in some subjects to suffer from, A predisposition that has helped promote research on genes that may explain this relationship.

Seven genes recently linked to anxiety

Recent research has attempted to find a link between certain genes and the existence of anxiety disorders or symptoms related to anxiety.

In this sense, it should be borne in mind that although it is a question of specific genes, the presence or absence of genetic predisposition does not depend on a single gene, but is considered polygenic. In other words, that is to say a gene alone does not mark a trait, but depends on the joint action of several genes and how they are configured across chromosomes.

1. Mmp9 gene (Matrix metallopeptidase 9)

In this gene, anxiety has been analyzed and linked to four haplotypes or mutations and different combinations of specific alleles. According to previous studies, this gene is involved in coronary heart disease and cancer, which correlates positively with regard to both anxiety as a predisposing element to suffer because of the knowledge of the disease.

2. Bdnf gene (brain-derived neurotrophic factor)

A single haplotype of this gene, AGAT, has a high good association with a predisposition to anxiety disorders.. This gene contributes to cellular maintenance, allowing the modification of the synaptic space between neurons by the secretion of neurotrophins. It has also been associated with brain plasticity. It has been linked to the neurotransmitter serotonin, it also affects the proliferation of neurons.

3. Ntf4 gene (Neurotrophin 4)

This gene is involved in the modulation of synaptic space. It is essential for the survival and maintenance of neurons, being essential especially for striatals. More research is needed on its implication in anxiety disorders, but studies seem to indicate that it is involved in the vulnerability to these disorders, Especially if given in conjunction with the above

4. Nothing Egr2 and Egr4 (first answers 2 and 4)

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

5. Grm2 gene (glutamate receptor 2)

This gene is involved, as you can imagine from the name, in the reception and metabolism of glutamate., The greatest excitatory of the central nervous system. This link with glutamate makes this gene closely linked to anxiety disorders and even schizophrenia. In addition to anxiety disorders, it is linked to learning.

6. Arc gene (protein associated with the cytoskeleton with regulated activity)

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

Be careful! Be careful with biological determinism

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

To consider that having these genes means suffering from an anxiety disorder would be wrongAs it can make us forget the shaping influence of the environment and education, elements that can arouse or ignore the biological predisposition. And it is that anxiety disorders, like the rest of 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 on the disorders, both anxiety and otherwise.

Bibliographical references:

  • American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders. Fifth edition. DSM-V. Masson, Barcelona.
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  • Wade, N. (2014). The identification of new susceptibility genes involved in anxiety disorders. Stellenbosch University

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