Atmosphere Sato (Doctoral student) and Professor Masakado Kawata of Tohoku University have detected genes related to "individuality of the heart" that have evolved favorably by natural selection in the evolutionary process of human beings. bottom.
Mental illness affects about 2% of modern people and has a high heritability.It has become an important issue in psychiatry, neuroscience, and evolutionary biology.On the other hand, many recent studies have found considerable overlap in the genetic background of mental illness and mental personality.There is also research suggesting that genetic variation related to individuality can be actively maintained, but there is no clear evidence.
In this research, we focused on genes related to psychiatric disorders and detected genes that evolved at an accelerated rate during human evolution using the genome sequences of 15 species of mammals.We also attempted to identify genetic variants that are actively maintained in the population using genetic polymorphism data from about 2500 modern humans.
As a result, it was found that the three genes evolved at an accelerated rate by natural selection during the evolutionary process of humankind.Among them, the 3th amino acid of the gene "SLC18A1" differs from person to person, and it was found that there are three genotypes.In addition, genetic changes in the SLC136A3 gene during human evolution may have affected human mental function, and previous studies have shown that depression, anxiety, and nervousness, as well as bipolar disorder and schizophrenia. It has been pointed out that it is related to such things.
Furthermore, genotypes showing anxiety and nervous tendencies are said to have had a favorable effect on the early stages of human evolution, and when humans spread to the world, genotypes showing antidepressant / anti-anxiety tendencies are naturally selected and advantageous. It is presumed that it has evolved.
The evolutionary findings of this study are expected to give suggestions on individuality, the biological significance of psychiatric and neurological disorders, and the direction of treatment.
Paper information:[Evolution [Letters] Positive and balancing selection on SLC18A1 gene associated with psychiatric disorders and human-unique personality traits
