Objectives: Besides psychological and social effects, biological, biochemical and genetic factors also play a role in the background of suicide. The aim is developing a complex model incorporating all the above factors so that suicide could be predicted and prevented in those at risk. Based on several studies 5-HTTLPR s allele frequency is increased in case of violent completed suicides. The aim of the present study was to validate this association in a sample of completed suicides.
Methods: During autopsy sample DNA samples were obtained for 5-HTTLPR genotyping from 200 subjects deceased due to suicide and 200 controls deceased due to other causes. Chi square tests and logistic regressions were performed according to additive, dominant and recessive models to analyse the possible association between 5-HTTLPR genotype distribution and suicide.
Results: Ratio of violent and non-violent suicides was 81% and 19% respectively. No significant difference was found in the distribution of 5-HTTLPR genotypes between the suicide and controls samples. No difference was found between violent and nonviolent suicides with respect to genotype distribution. A significant association was found between sl genotype and suicide at a younger age.
Conclusions: Our pilot study did not support the supposed association between 5-HTTLPR and completed suicides or with violent completed suicides. However we found a significant association between sl genotype and suicide in young suicidals.