The range of mental illnesses, including children’s ones, is quite extensive, the list of those that are inherited is much more modest. However, psychogenetics – the science that studies mental disorders with genetic roots – is only decades old. Despite numerous experiments and research, it is still in the realm of speculation, not discovery. Children with mental disorders are a key topic of geneticists, since the main parameters for the formation of a future personality are laid in the womb and largely depend on hereditary indicators.

Children: hereditary mental disorders

To begin with, it is worth listing mental illnesses of presumably genetic origin, including:

• Dysgraphia, dyslexia, dyscalculia (specific learning disability or specific learning disorder)
• Attention Deficit Hyperactivity Disorder (ADHD)
• Autism
• Affective insanity
• Schizophrenia

The whole difficulty of identifying a particular disease consists in determining the gene responsible for it and the region of the chromosome. But this is not the only difficulty. Each gene is accompanied by epigenetic units, which also carry certain information, but do not change the gene itself. Epigenetic changes can also be transmitted from generation to generation, and sometimes (under a certain set of circumstances) can manifest themselves at the biochemical level and cause the same mental abnormalities.

The method used by geneticists to identify the “offending gene”, namely molecular genetic analysis, is also imperfect. In the best case, it will allow identifying mutant genes, possibly affecting mental abnormalities. That is why one should be very careful about the next discoveries of the gene for alcoholism, aggression, antisocial behavior, and genius.

Children act as a relatively suitable subject for genetic research, identifying disorders of mental factors is a little easier than in adults. 

Child Development: Attempts to Diagnose Mental Disorders

Diagnosing hereditary mental illness in children is not easy. Many of them have similar symptoms. Geneticists conduct research from a qualitative and quantitative point of view: on the one hand, the percentage of the disease is calculated, that is, the frequency of its manifestation, the age characteristics of the sick, on the other hand, changes in the genome are directly investigated. As a result, each of the diseases acquired its own “markers” and distinctive features that accompany the development of the child at different stages . 

For example, it is most difficult to identify specific learning disabilities in children. This mental disorder can be accompanied by unusual emotional responses to both the subject matter and the environment. Hence the unpredictability of the behavior of children with this developmental defect during classes. This disease is detected at the time of learning to read, write and count: there is a discoordination between writing what was heard and reading what was written. Someone, on the contrary, is given reading and writing, but not given an account. Problems with memory and concentration may also be to blame. Children with a specific developmental disorder of academic skills due to the above-mentioned defects do not perceive and absorb information poorly.

The statistics of morbidity in children with a specific disorder of the development of educational skills is very relative – in Russia such deviations of the psyche make up 20-30%. Presumably, they are all caused by a change in one of the regions of chromosome 6.

Attention deficit hyperactivity disorder (ADHD) has similarities to the specific developmental disorder of learning skills. The incidence rate here is much less (6-10%), but the genetic predisposition reaches 40%.

The detection rate for autism is on the rise. Autism spectrum disorders are usually congenital disorders and can occur very early in a child’s development. Sometimes the disorder may not reveal itself for a long time, and it may arise already in an adult state under the influence of certain external factors.

As for manic-depressive psychosis and schizophrenia, then these diseases can occur at any stage of a child’s development. At the same time, in addition to the congenital factors of these diseases, external influences, including viral infections, cannot be discounted.

Despite all attempts to classify hereditary mental illnesses by signs and age scale, it has not yet been possible to develop a unified system. In any case, mental disorders affect the emotional and intellectual development of the child, as well as motor functions. 

Children: symptoms of mental illness

Consider the differences in mental disorders in children.

Children with a specific developmental disorder of learning skills are characterized by excitability, restless activity, and repetition of movements, combined with absent-mindedness and inability to concentrate. Due to academic failure, children with this diagnosis may experience an inadequate response to the school environment, which explains the oddities in their behavior. Children with specific learning disabilities appear to have brain dysfunctions, although they do not suffer from intellectual disabilities.

The set of external manifestations in children with ADHD syndrome is fully expressed in the very name of mental illness – attention deficit with high physical activity.

Symptomatic manifestations of manic-depressive psychosis in children form a very contradictory picture. This mental disorder is characterized by dramatic contrasts and swings in mood and behavior. Activity and excitability can be interspersed with melancholy and unreasonable fear, agitation (excitement) can replace melancholy. This disease is marked by a lowered self-preservation instinct and a spontaneous, unreasonable nature of actions.

In schizophrenia, mental disorders are associated with the emotional sphere, peculiarities of thinking, perception, behavior, defects in the motor system and intellectual activity. The manifestation of signs of this disease in children is often mixed. This disease can be limited to one single attack (and respond favorably to the therapy), or it can manifest itself constantly. In this case, the loss of personality can occur unnoticed by others. Under the guise of indifference, for example, states that destroy the psyche can ripen, leading to the disintegration of the personality and its loss from society.

Child mental development: genetics versus external factors

Let’s summarize. Despite the facts that indicate the natural, congenital nature of mental disorders in children, there are as many arguments on the side of external circumstances: living conditions, methods of upbringing and education, the degree of favorable environment. Many experiments allow us to conclude that an atmosphere of well-being, care and attention is important for the mental development of a child. It is because of the lack of external comfort that an internal conflict arises, aggravating the child’s mental development with various kinds of deviations.  

Foster children with a burdened mental heredity deserve special attention. Parents who decide to adopt a child should not be intimidated by this circumstance. It is much more important to have complete information about the child’s pedigree in order to direct the child’s mental development in a favorable direction with the help of specialists and avoid possible disorders and difficulties in upbringing.

Now let’s move on to the numbers. Today the number of hereditary diseases reaches 2,000. Among young children, the proportion of children with various kinds of mental disabilities is about 25%. By the age of 6, their number drops to 17%. This is explained by such an important factor as the natural development of the child and the positive impact of society.

It can be concluded that the main goal of a child’s development is the successful realization of the hereditary qualities inherent in him. And it is desirable that upbringing was not a hindrance, but a way to successfully implement the task set for the full and mentally normal development of the child.