Scientists have already discovered at least a few genes that may be associated with the occurrence of schizophrenia. Some reports say that mutations lead to changes in the amount of neurotransmitters in the brain, while others argue that genetic disorders can impair brain plasticity. The relationship between genes and schizophrenia may also be evidenced by the fact that if someone from a given person's family suffers from schizophrenia, he or she is at increased risk of developing this disease.

Schizophreniais considered to be one of the most severe psychiatric diseases. During it, the whole psyche of the sick person is disorganized - hence the name of this disease, as it is derived from the Greek words schizein (to split) and phren (mind).

Because schizophrenia can impair patients' lives, as well as the - not uncommon - difficulties encountered in the treatment of schizophrenia, scientists are still analyzing the underlying factors. There is probably no one specific cause of schizophrenia - the etiology of this unit takes into account, inter alia, infections experienced by patients during their intrauterine life, but also patients' use of psychoactive substances in the early stages of life. Another aspect that can potentially cause schizophrenia is genetic disorders.

Inheriting schizophrenia: are genes related to schizophrenia?

The population prevalence of schizophrenia is estimated at around 1% and it is similar in different regions of the world. The existence of such a relationship may, therefore, suggest that environmental factors (related to the place of residence of patients) actually play a minor role in the pathogenesis of schizophrenia. The attention of researchers is therefore directed to other potential causes of this disease, including towards genes and disorders related to them.

The effort put into the research conducted so far has not been wasted - it has been possible to detect certain genes, the mutations of which may favor the development of schizophrenia. One such gene is the COMT gene, which encodes the enzyme catechol-o-methyltransferase. This protein is responsible for the metabolism of neurotransmitters, including dopamine. It has been noticed that mutations in the COMT gene can leadchanges in the amount of dopamine in the brain - and it is the disturbances in the amount of this neurotransmitter that are found in patients with schizophrenia.

Another gene that appears to be associated with schizophrenia is DISC1. This gene even has a name derived from the disease in which pathogenesis can participate - the DISC1 abbreviation comes from the English phrase "disrupted in schizophrenia", which can be translated as "damaged in schizophrenia". In studies conducted on mice, it was noted that mutations of this gene change the so-called plasticity of the brain. This feature is particularly important because it allows the mind to adapt to changing environmental conditions - thanks to the plasticity of the brain, for the formation of new neural connections. It is believed that abnormalities in brain plasticity - which may be due to a DISC1 mutation - may increase the risk of developing schizophrenia.

Another gene that has recently been mentioned in the analysis of the links between genetic disorders and schizophrenia is the C4 gene. The protein product of this gene is involved in the degradation processes of interneuronal connections. Such phenomena even take place completely physiologically - changes in the connections between individual nerve cells take place, for example, during the processes of human maturation. However, mutations of the C4 gene may lead to excessive degradation of the mentioned connections, and thus contribute to the emergence of schizophrenia.

Inheriting schizophrenia: are there tests that detect genetic disorders associated with schizophrenia?

Currently, there are no commercial tests that would allow us to determine whether we have a genetic disorder predisposing to schizophrenia. Such research could be of particular interest to those who have someone suffering from schizophrenia in their family - after all, their risk of developing the disease is higher than the population risk of 1%.

There are at least a few reasons why there are no genetic tests to determine the risk of schizophrenia. The first to be mentioned is that science still does not have enough knowledge about the genetics of schizophrenia. Indeed, as mentioned above, some genes potentially involved in the development of this disease have already been discovered, however, the reports currently available can be taken as assumptions rather than certainty. It should also be taken into account that the family history of schizophrenia does not mean that the disease will recur in other members of the family in the future. Indeed, in the presence of schizophrenia in relatives, the risk is thatwe get sick, it is (sometimes even significantly) increased, but it still does not mean that such a patient has the same genetic disorders as his relatives. After all, the percentages given above are still only a statistic.

Another aspect that probably will not see genetic testing for schizophrenia on the market is the pathogenesis of the disease itself. It is believed that the etiology of schizophrenia is multifactorial and that the disease develops only when several different pathologies overlap. It should be remembered that genetic disorders may actually contribute to schizophrenia, however, they are not the only factor triggering the occurrence of this disease in patients.

Worth knowing

Inheriting schizophrenia: are we at increased risk of having a relative with schizophrenia?

The role of genetics in the development of schizophrenia may also be convinced by the fact that the risk of this disease is higher if a member of a given person's family already suffers from it. The risk varies and is directly related to the degree of kinship with the patient with schizophrenia.

The greatest risk concerns identical twins: when one of them suffers from schizophrenia, the risk of the same disease in the other twin is almost 50%. In other cases, the risk may be as high as: -5% if one of the grandparents suffers from schizophrenia, -6% if a brother or sister suffers from it, -13% if one of the parents has schizophrenia, -46% if one of the parents has schizophrenia, when both parents have schizophrenia.

Category:

Psychiatry