Genetics of Adolescent Suicide: A Literature review
Adolescent suicidal behavior is a global public health issue; however, genetic studies are sparse and diverse. A review of the current knowledge on the genetics of adolescent suicide based on an electronic search of two databases is being presented, following PRISMA guidelines. After identification, screening, and exclusion, 17full-text articles based on original studies were included for the review. Studies indicate significant heritability for suicidal behavior. Aggression was found to be associated with higher rates of suicide attempts within families. Possible genetic variants, environmental changes, their interaction, and the timing of these interactions appear to be critical in deciding the suicidal behavior. Several candidate genes and pathways have been implicated with a focus on neurotransmitters, neurotrophic processes, stress response system, and the immune system. From the results, the serotonergic system seems to be the most plausible system explaining anxiety, impulsivity, depressed mood, and adolescent suicidal behavior. However, inconsistencies for serotonergic genes were also reported for adolescent suicidal behavior which largely reflected the ethnic and phenotypic variation. The serotonin transporter variant was significantly associated with depression and suicide attempts while serotonin receptor gene variants were significantly associated with suicide ideation. Tryptophan hydroxylase variant had a significant association with suicide attempts, hopelessness, and impulsivity scores. Majority of the studies had a small sample size, and the lack of consensus on genetic studies reflected the phenotypic and ethnic variation. We need to develop a consortium for ethnic-specific observation by considering both genetic and epigenetic background and develop a consensus strategy to resolve phenotypic diversity for adolescent suicide.