Schizophrenia is one of the most complex psychiatric pathologies, the complexity of which is due to the unclear etiology and unpredictability of the course. The exact causes of its occurrence are unknown. Scientists talk only about the factors that increase the likelihood of its development. Inheritance is one of them. Find out if schizophrenia is really inherited and how it happens.


Opinions of Scientists

In the literature on schizophrenia, there are different data regarding its causes. There are even separate theories in which scientists conduct their research and try to confirm or refute certain hypotheses. Some of them:

  • Dopamine. Increased production of dopamine, melatonin and serotonin leads to the appearance of delusions and hallucinations in a person.
  • Infectious. Chronic viral diseases, as well as streptococcal, staphylococcal and tuberculosis infections reduce immunity and cause mental disorders.
  • Neurogenetic. A defect in the corpus callosum, which connects the left and right hemispheres, leads to disruption of the coordinated work of the brain.
  • Ecological. Environmental pollution negatively affects the development of the embryo, causes a lack of vitamins, and ultimately increases the likelihood of developing psychiatric pathologies.
  • Psychoanalytic. A bad relationship with a despotic father or a strict mother, a cold atmosphere in the family, etc. can lead to the onset of the disease.
  • Evolutionary. The increase in intellectual abilities due to technological progress does not coincide with the natural capabilities of the brain. Nature tries to adapt to change, but sometimes fails.
  • Traumatic. Mental disorders can cause various types of trauma, including postpartum and surgery.
  • Genetic. If there is at least one person with schizophrenia in the family. others are more likely to develop it.
See Also: Here’s Everything You Need to Know About Schizophrenia

At the same time, disagreements can be within the framework of each of the listed theories. Some scientists claim the existence of 74 or even 100 genes that are responsible for schizophrenia, other researchers are more restrained in their conclusions, believing that accurate data on this issue have yet to be revealed.

In general, doctors have found a set of genes that can affect the functioning of the brain. But it is difficult to draw a direct link between them and schizophrenia. This is not the case when researchers took DNA, studied it, decomposed genes into dominant and recessive, and found the exact chain that influenced the development of the disease. In any case, the conclusion about genetic conditioning will be an assumption, not an exact scientific fact.

Today, there are 3 main approaches to studying the hereditary factors of schizophrenia:

  • Genetics is necessary to study differences in the structure of genes.
  • Pharmacogenetics, allows the correct use of therapy, prescribing appropriate drugs, and reducing side effects.
  • Study of the genesis, aimed at studying the etiology of the disease.

In addition to studies in the genetics of schizophrenia, which do not always confirm hypotheses, scientists have statistics at their disposal that indicate that genetic factors should be studied without fail.

Schizophrenia Inherited

Statistical Data

In general, schizophrenia is detected in approximately 0.5-1% of people, that is, no more than one person out of 100. As for the risks of the disease and the percentage, they are presented as follows:

  • 1% – the first case in the family.
  • 2% – sick uncle / aunt, nephew or cousin brother / sister.
  • 5% – the disease was in the great-grandmother or great-grandfather.
  • 5% – a sibling suffers from pathology.
  • 10% – a brother or sister or relatives of 1-3 lines are sick.
  • 10% – the diagnosis was made to the grandparents.
  • 20% – dad or mom has a pathology.

At the same time, the probability of developing pathology in a child from two schizophrenic parents is 45-60%. Among twins, the statistics are as follows: 13-17% are dizygotic, and 47-48% are monozygotic.

As you can see, the closer the degree of relationship, the greater the risk of the disease. However, to say 100% that two parents with schizophrenia, the child will suffer from this pathology, is wrong. There is a chance, but not as high as many belief.


Relatives of Patients

According to modern genetic research, not only specific pathologies are genetically predetermined, but various aspects of the personality, such as a high level of anxiety or, on the contrary, excessive calmness and shyness. Aggression tendencies, alertness, sensitivity to criticism, and the ability to respond to new circumstances may also be inherited.

Such data can be obtained from studies of identical twins who are brought up in different conditions. Even with different upbringing, common traits of character and temperament can be traced. And this applies even to the love of risk and adventure.

In general, the genetic factor plays an important role in pathologies such as schizophrenia and autism. It is also subject to close study in the analysis of various affective disorders and hyperactivity. At the same time, scientists find not only behavioral similarities but also biochemical and immunological ones.

This means that the composition of the blood, the number of lymphocytes, and other biological parameters in patients with schizophrenia largely coincide with similar data in their relatives, even if the latter do not have psychiatric disorders.

See Also: What Is Catatonic Schizophrenia?

Scientists propose to consider 3 categories of relatives who have patients with schizophrenia in the family:

  • People with schizoid traits – isolation, loneliness, focus on the inner, and not on the outside world.
  • Persons with schizoid features and with a pronounced emotional defect.
  • Personalities with schizoid features with affective disorders (bipolar phase change, seasonal depression, etc.).

Statistics show that about 20-30% of first-degree relatives of people with schizophrenia complain of certain symptoms. In this case, there is no diagnosis, and therefore they speak of the so-called “spectral disorders”. Symptoms are rather weak and more indicative of isolation, vulnerability, and low emotional intelligence. They are observed in many schizophrenics, especially before the onset of an attack.


Cognitive abilities of relatives of patients

Among the relatives of patients with schizophrenia, if we talk about the cognitive (cognitive) sphere, the following patterns are observed:

  • Altered psychomotor speed.
  • Violation of visual and short-term verbal memory.
  • Attention instability.
  • The unusual formation of judgments (abstractness).
  • Difficulties in organizing an action plan.
  • Difficulty copying images.

But this does not apply to all relatives. Most people either do not have these signs or compensate for them with sufficient intellectual activity. However, it is wrong to exclude the presence of these regularities in the analysis.


Structural changes in the brain

Another type of research involves structural and functional changes in the brain, which are recorded in relatives of patients with schizophrenia. In particular, we are talking about the following features:

  • Expansion of the third and lateral ventricles.
  • Reduction of the thalamus.
  • Dysmotility of the eye muscles.

These data are obtained by implanting electrodes, tests for antisaccades (eye movements behind an object), electrophysiological and other studies.


Influence of the male line

In men, schizophrenia manifests itself earlier and is accompanied by more obvious signs. Therefore, it is important for doctors to understand whether it is inherited more often from the father than from the mother. In general, the following patterns are observed:

  • Men are prone to psychiatric pathologies already in childhood or adolescence.
  • These diseases progress rapidly.
  • An insignificant factor can become an impetus for the development of a disease or an attack.
  • Men, in principle, are more prone to neuropsychic overload.

However, practice shows that despite all these facts, schizophrenia is often inherited from a woman. But because of the severity of the symptoms, it seems that men suffer from this psychosis more often. This leads to the formation of a stereotype about the male nature of the disease. But in reality, women get sick with it no less often, just the first signs appear later – after about 6 years.

In addition, there are other factors that increase the risk of developing schizophrenia. Among them are alcoholism and drug addiction, which are more often observed in the representatives of the stronger sex. Also, men turn to doctors less often, and therefore the pathology progresses for a long time without any medical intervention in this process.

All of these factors increase the risk of developing mental illness. However, this does not mean that it is passed from father to son. Although this possibility should not be ruled out. Just the mechanism of transmission of the disease still remains unknown.


Influence of the female line

The risk of getting schizophrenia through the female line, that is, from the mother, is 5 times higher than from the father. But the transmission mechanism, as in all other situations, is unknown. Scientists have only specific clinical cases. Therefore, it is impossible to say for sure whether a woman with schizophrenia will have children with schizophrenia or not. Although you still have to exclude other risks in order to reduce the percentage of probability.

There is an assumption that a woman may be a carrier of a chromosomal mutation that will cause the development of schizophrenia in her child. At the same time, she herself may not get sick. So, for example, it often happens with color blindness, which is more often detected in men, but the gene for this disease is often transmitted from women.

A provoking factor in the occurrence of schizophrenia can be an infectious or respiratory disease suffered by the mother during gestation. Also during this period, toxicosis and alcohol consumption are dangerous. They, in principle, adversely affect the state of the embryo. It turns out that there is a risk of brain damage, which can subsequently cause schizophrenia.

In this context, it is important to consider the social causes of pathology that are associated with a woman. We are talking about the difficult conditions for the development of the child and the lack of full-fledged care for him. But in any case, schizophrenia becomes the result of many reasons, which should include biochemical pathologies, organic brain damage, etc.


How to influence genes

So, the inheritance of the pathology in question is an assumption that is not exactly supported by scientific data. Genetic conditioning is considered one of the provoking factors. To date, there is no identified gene that would accurately lead to this disease. In most cases, we are talking about a set of genes that can hypothetically be the impetus for the development of schizophrenia.

But is the predisposition itself, when there is such a diagnosis in the anamnesis of relatives, a “time bomb”? Is it worth it for a person whose grandmother, mother, or sister suffers/suffered from this disease to constantly check their mental health?

Consider the example of alcoholism. No doctor can name the exact reasons for it either. There is always a group of factors, despite the fact that many researchers claim to have found the gene for this disease. Even if this is so, it is not possible to influence him.

See Also – Insulin Coma in Schizophrenia

Moreover, almost 50% of alcoholism is caused by the environment. If there is also a genetic predisposition, then this percentage becomes slightly higher. But to influence this, that is, to prevent the disease, is possible only by influencing social factors: do not visit places where they drink a lot, lead a healthy lifestyle, come to consult a psychologist, etc.

In almost all cases, there must be a push for the wrong genes to show up. If this provoking factor does not exist, it is possible that a person even with a large set of genes that hypothetically cause schizophrenia will live a quiet life without any hint of psychiatric disorders.

Here is another example directly related to the disease in question. Imagine identical twins whose genes are the same. If one of them develops schizophrenia, then the risk of falling ill with it for the second is less than 50%. This means that there are other reasons that are not related to heredity.


Lack of predisposition

About 10% of patients with schizophrenia do not have a genetic predisposition. At least, none of the relatives in several generations can identify it. Physicians can examine the history of all relatives, which will be provided. It is not a fact that signs of a mental disorder will be found, in principle.

This means that people who hypothetically should never get sick, according to supporters of the genetic theory, are also at risk of experiencing this pathology. Moreover, 10% of patients, about which the statistics speak, is a fairly high figure.


Other risk factors

People who have schizophrenic relatives are advised to rule out other risk factors. If you are a carrier of genes that cause schizophrenia, you should play it safe and take all possible measures to prevent pathology. Some of the risk factors have been described above in the theories and hypotheses section. We list the psychological and social reasons. Among the first:

  • Closure, focus on your inner world.
  • Passivity, suspicion, stubbornness.
  • Tendency to lengthy reasoning.
  • Difficulty in formulating thoughts.
  • Inadequacy of emotional reactions.

In the last paragraph, we are talking about situations where unimportant events greatly affect a person, and serious tragedies do not cause any emotional response. These symptoms may indicate a person’s susceptibility to schizophrenia. If they are present in a child, it should be shown to a psychologist or psychiatrist.

Social factors, which are understood as the influence of the environment, include:
  • Uncomfortable living conditions – overcrowding of the city, a large number of people in the apartment. All this leads to high levels of stress.
  • Social status. If it is low, and the person does not have a good job and income, the likelihood of psychosis increases.
  • Negative family relationships. We are talking about conflicts, excessive hostility, suspicion, constant criticism, etc.

The causes of schizophrenia can be listed almost endlessly:

  • Alcoholism, drug addiction, sexual or other violence, injuries, etc.
  • In addition, it should be understood that this pathology is diverse.
  • It takes a variety of forms – paroxysmal, paranoid, sluggish, etc.
  • Some patients with such diagnoses live a normal life, while others die or become incapacitated.

However, in all cases, it is recommended to start treatment as early as possible. To do this, you need to detect the first signs in time. A large role in this is given to relatives, through whose efforts it is often possible to bring a person to the first examination.


Main symptoms

Symptoms are determined by the type and form of the disease. However, there are a number of signs that are characteristic of almost all varieties of this pathology:

  • The openness of thoughts. It seems to a person that all his thoughts are available to others.
  • Problems with thinking. Often schizophrenics are prone to lengthy reasoning. At the same time, they constantly get confused, and confused and cannot fully formulate what they want to convey to others.
  • Rave. It seems to the patient that someone else controls his thoughts, actions, and feelings.
  • Hallucinations and pseudohallucinations. The latter differs from the former in that a person does not identify images, voices, sounds, and smells with real-life objects and objects.
  • Emotional disorders. As a rule, patients have a tendency to apathy and pathological experiences.
There are less obvious signs, which are called negative (negative) symptoms, indicating a decrease in mental activity:
  • Lack of initiative;
  • Decreased memory and attention;
  • Fast fatiguability;
  • Loss of interest in something;
  • Lethargy or lack of facial expressions;
  • Isolation and a tendency to loneliness;
  • Inability to enjoy life.

In adults, there is a loss of communication abilities, professional unsuitability, and suicidal behavior. In children, the following signs of the disease can be noticed:

  • Inexplicable fear. The child refuses to go into the room or approach this or that place, screams, rests, and throws tantrums for no apparent reason. Often, children with this diagnosis tell stories about scary creatures and even show the places where they are.
  • Weird fantasies. During stories about heroes of films or comics, the child is so immersed in his role that he cannot get out of it for a long time.
  • Decreased intelligence. He becomes less attentive, poorly remembers new information, and his performance at school falls.
  • Strange actions. The child constantly looks around, listens, or whispers the time. It is possible that he hears voices and does not understand that they are only in his head.
  • Inappropriate emotions. Expresses them disproportionately to the situation. Cries laughs, rejoices, or is upset when there are no objective reasons for this.
  • Manifestations of cruelty. The child becomes more aggressive and less likely to communicate with peers, and he has a tendency to violence against animals or toys.

Some of these signs in one form or another can be found in healthy children with poor education. It is important not to ignore them, since schizophrenia, which began early, leads to more serious consequences than the same pathology that occurs in an adult.


When it appears

Medical practice shows that the risk of developing schizophrenia decreases with age. According to statistics, the disease manifests itself with the following frequency:

  • 10-20 years – 17%.
  • 20-30 years old -39%.
  • 30-40 years old – 26%.
  • 40-50 years old – 14%.

To be more precise, at first, the risk becomes higher and higher. This continues until the age of 30. Subsequently, the likelihood of getting sick is much less. However, it can manifest itself both a few years after birth and in old age. The risk is less, but it still exists.


What to do

So, schizophrenia can be congenital (hereditary) and acquired. No doctor can name the exact reasons. If you have a genetic predisposition, you should not be afraid of the disease all your life. However, if possible, other risk factors should be removed.

Schizophrenia has no cure. But this does not mean that you can leave it unattended or, on the contrary, despair. In many cases, doctors manage to stop the symptoms of the disease forever or for many years. The main thing is to start treatment immediately in order to prevent a serious defeat of the personality or its complete destruction.

Science does not standstill. Perhaps in 10-20 years, scientists will find a way to completely rid a person of this dangerous disease. However, the disease can be reversed only if the unhealthy personality has not supplanted the real one. With a serious schizophrenic defect, a person loses his legal capacity. There is a possibility of death.