Serotonin transporter gene promoter (5-HTTLPR) and intron 2 (VNTR) polymorphisms: a study on Slovenian population of suicide victims

Several studies have been carried out to investigate how genetic variants of gene encoding for the serotonin transporter (5-HTT) may confer susceptibility to suicide. It was demonstrated that polymorphisms in the promoter region (5-HTTLPR) and in the second intron (VNTR) have functional consequences and are for this reason of particular interest in relation to various psychiatric disorders. In our study, we analyzed 5-HTTLPR and VNTR polymorphisms in 235 suicide victims and 233 controls in a Slovenian population to find a possible association of the polymorphisms and suicidal behavior. No statistically important differences between genotypes of controls and suicide group (5-HTTLPR: Pearson's chi(2) = 1.597, df = 2, P=0.455; VNTR: Pearson's chi(2) = 1.961, df = 4, P= 0.744), as well as no differences in allele distribution (5-HTTLPR: Pearson's chi(2) = 0.598, df = 1, P = 0.467; VNTIR: Pearson's chi(2) = 0.837, df = 2, P = 0.654) were found, although a slightly higher frequency of LL genotype and of L allele was observed in the suicide group. Haplotype frequency analysis showed no excess of particular haplotypes between the two groups. Our study showed no association of serotonin transporter polymorphisms and suicide. The study, however, was performed on a population with a very high suicide rate (27.1 victims/100000 citizens) and the role of 5-HTTLPR polymorphisms may be different in other populations. Psychiatr Genet 16:187-191 (c) 2006 Lippincott Williams & Wilkins.