Systematic screen of serotonergic genes in suicidal behaviour

Family and twin studies point towards a partial heritability of suicidal behavior. We investigated the role of a comprehensive set of serotonergic candidate genes in this behavior. Their selection was driven by results from post mortem and genetic studies. 150 suicide attempters with various psychiatric disorders were compared with volunteers which were randomly selected from the general population. 320 healthy control subjects without relevant somatic and with no psychiatric disorder were included. All subjects were administered standard psychiatric interviews including SCID as well as self-report questionnaires for anger-related traits. The distribution of genetic polymorphisms in the ABCG1, TPH, 5-HT1B, 5-HT2A, SERT, and MAOB genes was examined. For anger-related traits, a multivariate effect of the A218 SNP in the TPH gene and an interaction effect for genotype and diagnosis was observed in healthy volunteers and suicide attempters after controlling for age and educational level. A meta-analysis provides strong evidence for an association of suicide-related behavior with the A218 SNP in the TPH gene in Caucasians.