Biology of suicidality. Twins and suicides

Freely available information in the PubMed database on suicidal behavior of twins was collected and analyzed. In the literature review, data are stratified into thematic sections on the difficulties of determining heritability when assessing the suicidality of twins, predictors of their suicidal behavior, analysis and comparison of registry studies of suicidal behavior and its associations with genetic factors, gender stratification of suicidal behavior, suicidal behavior in twins with mental disorders, results case-control gene association studies and genome-wide studies of their suicidality. The genetic and epigenetic causes of discordance in monozygotic twins are considered. The pool of studies that has been formed to date allows us to conclude that suicidal behavior in twins is heritable and early manifests itself as a complex of verbal behavioral predictors. The basis for the formation of suicidal behavior is the accumulation of single nucleotide polymorphisms in the genome, the expression of which is associated with the formation of personality and its traits such as increased aggressiveness, hyperactivity, and attention disorder. Suicidal behavior and severe mental disorders (bipolar depression, schizophrenia) are comorbid, but generally not associated.