How is schizophrenia different from bipolarism

Do schizophrenia and manic depressive disorder have the same cause?

Schizophrenia and bipolar affective disorder, better known as manic-depressive disorder, are some of the most common mental illnesses. Even if environmental factors are considered to be the main triggers for both diseases, the disorders only occur if certain genetic predispositions are present. Sabine Bahn from the University of Cambridge was able to explain the nature of these dispositions together with British and American colleagues.

The researchers examined the brains of fifteen schizophrenic, manic-depressive and healthy patients to determine which genes were active and which were switched off. The comparison of the gene profiles showed that in all the brains of the sick the same group of genes was less active than in those of healthy people. These genes are responsible for the formation of myelin, a protein that lies like an insulating layer around nerve cells and is crucial for the correct transmission of electrical nerve impulses.

The similarity of the gene profile changes supports earlier assumptions that the two diseases may be more closely related than previously assumed. However, the researchers have not yet been able to explain why such different diseases develop from the same disorder. For example, schizophrenic patients often show a loss of reality with hallucinations and delusions, while manic-depressive people fall from phases of extreme euphoria with increased drive and disinhibition into deep depression.

ddp / bdw? Ilka Lehnen-Beyel
September 5, 2003

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