Natural selection is to blame for the spread of schizophrenia
Genes responsible for the development of schizophrenia, have some unknown advantage, which allowed them to gain a foothold and spread in the course of evolution, according to the journal Proceedings of the Royal Society B.
Schizophrenia is inherited
Canadian scientists from the University of Simon Fraser (Simon Fraser University) investigated 76 DNA sites associated with the development of schizophrenia. At the same time, human genes were compared with corresponding genes of monkeys (chimpanzees and macaques), as well as mice, rats, cows and dogs.
It turned out that 28 of the 76 genes studied were very persistent and passed down from generation to generation. In the process of transferring genes, they underwent changes much less frequently than DNA segments taken as controls.
High resistance of schizophrenia genes in the process of evolution is confirmed by existing data. This mental illness, capable of being passed down from generation to generation, is diagnosed in about 1% of the world’s population.
The head of research, Bernard Crespi (Bernard Crespi), explained that the fixation and distribution of a gene in populations occurs when it encodes a trait that is useful for one organism or another. This can happen in the case of genes associated with the development of diseases. In particular, it is known that a gene mutation that promotes the development of cystic fibrosis protects a person from cholera, and people suffering from sickle cell anemia are resistant to malaria. The “genes of schizophrenia” can also give their carriers a certain evolutionary advantage, the researchers suggested.
Scientists still do not know what kind of advantage these genes give. Some psychiatrists believe that people with schizophrenia are characterized by a rich imagination and developed creative abilities. Perhaps these characteristics help their carriers to adapt to different life situations and it is easier to find a pair.
The researchers themselves point out that from the point of view of genetics, the relationship between schizophrenia and creativity does not look very convincing.
The search for notorious advantages is hampered by the fact that different genes are responsible for the development of schizophrenia in different nations. Only four of the 28 persistent DNA fragments found by scientists were distributed on more than one continent, the researchers said.