Smoking activates the gene for schizophrenia
Last reviewed: 23.04.2024
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Smoking helps to manifest one of the genes responsible for the architecture of the brain; some variants of this gene increase the likelihood of developing schizophrenia, so that if they are present, smoking becomes one of the risk factors for this disease.
Since it became known about the hereditary nature of schizophrenia, scientists do not abandon attempts to find the genetic causes of the disease. It can not be said that these attempts are unsuccessful, but the set of mutations that can lead to schizophrenia grows with each passing day, and it is extremely difficult to single out the main one in some main gene.
Investigating the genetic causes of schizophrenia, usually compare the frequency of occurrence of dangerous variants of genes in healthy people and patients. Scientists from the universities of Zurich (Switzerland) and Cologne (Germany) have added an electroencephalographic test, which allows you to see how the brain processes sound signals. A healthy person can distinguish from many sounds one, the most important, and discard the rest as unnecessary noise. In schizophrenia, this ability is lost: the brain loses its ability to filter acoustic signals and eventually drowns in the flow of information. However, in healthy people such processing of sound information is expressed in different ways: someone gets it better, someone worse. Comparing such brain activity with the presence of one or another form of the gene, one can say what role this gene plays in the development of schizophrenia.
In this case, the researchers were primarily interested in the TCF4 gene, which encodes one of the transcription factors. This protein is involved in the development of the brain in its early stages, and it is believed that some variant forms of this gene may not have the most beneficial effect on the developing brain. In addition, TCF4 activity is not necessarily limited to the initial stages of the body's life. The experiment was attended by 1,800 people. It should be noted: the researchers took into account the fact that there are many smokers among schizophrenic patients, and therefore paid special attention to the relationship between the disease and the intensity of smoking.
As scientists write in the journal PNAS, the TCF4 gene really influenced the ability of the brain to filter sound information: some forms of TCF4 accompanied deterioration of this function of the brain and were found predominantly in patients with schizophrenia. But the researchers drew attention to the fact that smoking greatly aggravated the situation. If the owner of the dangerous form of the TCF4 gene smoked, his brain showed a much worse result when processing the acoustic signal.
Here, according to scientists, we are confronted with the usual situation, when environmental conditions limit or, on the contrary, help the gene to manifest itself. The results obtained should help in preventing the disease: if a smoking person exhibits the first symptoms of schizophrenia, and at the same time he is not lucky with the TCF4 gene, it is in his best interest to quit smoking at all costs.
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