Suicidal behaviour is a serious problem world-wide. However, the number of risk factors and the complex nature of their interactions do not allow sufficiently accurate prediction of whether a given individual is likely to try to commit suicide. Several lines of evidence suggest that suicidal behaviour has a genetic component.

In recent years, a growing number of molecular genetic studies have focused on the serotonin system, suggesting that this system may be involved in the pathogenesis of suicidal behaviour, aggression, and impulsivity. Post-mortem studies have reported fewer serotonin transporter (5-HTT) binding sites and greater expression of serotonin 2A (5-HT2A) receptors in the brains of suicide victims compared to control subjects, partly due to functional polymorphisms that affect the expression of these genes.

In this the presentation we discuss data suggesting an association between the A-1438G (rs6311) polymorphism of the 5-HT2A receptor gene and the impulsivity of the suicidal behaviour. However, we found an excess of the -1438A allele in non-impulsive suicide attempts as compared with impulsive suicide attempts and with a healthy control group. These findings agree prior report by Giegling et al (2006) and suggest that this functional polymorphism may modify the phenotype of suicidal behaviour and could be related to the impulsivity of the attempt.