Interface of Polymorphisms of Serotoninergic System Genes with an Attempt to Commit Suicide


Lithuanian University of Health Sciences, Kaunas, Lithuania


Introduction. We have  analized one of the most common polymorphism C-1019G of the 5HTR1A receptor gene and two biallelic polymorphisms in intron 7 of the A218C and A779C genes. The 5HTR1A  gene encodes a G protein-coupled receptor for 5-hydroxytryptamine (serotonin). It plays a role in the regulation of dopamine and 5-hydroxytryptamine (serotonin) level in the brain, and thereby affects neural activity, mood and behavior. The tryptophan hydroxylase (TPH1) catalyzes the oxigenation of tryptophan to 5-hydroxytryptophan, which is then decarboxylated to serotonin.

The aim of our study is to investigate the association of the serotoninergic system genes SNPs (rs6295, rs1799913, rs1800532) within suicide attempters.

Methods. The study included 146 patients with F10(n=72/322) and F30-39(n=74/322) diagnosis hospitalized in the Psychiatry department of the Hospital of the Lithuanian University of Health Sciences after attempted suicides. Psychiatric disorders were identified according to ICD-10-AM criteria. A random sample (n=322) was formed according homogeneity from Kaunas population. The DNA was extracted from blood; its concentration was measured by spectrophotometry.  HTR1A and TPH1 SNPs (rs6295, rs1799913) were analyzed by real-time PCR. The results were calculated statistically by approved logistic regression and p<0.005 was considered as significant.

Results: Suicide attempters with affective disorders (F30- F39) and HTR1A (rs6295) G/G genotype and suicide attempters with mental or behavioural disorders due to alcohol use (F10) and TPH1 (rs1799913) G/T genotype had a significantly higher risk for suicidal risk.

The univariate logistic regression analysis to predict a suicide risk.Table 1.



OR (95% CI)

P value

rs6295 G/G vs C/C


2.158 (1.028-4.528)


rs179991 G/T vs G/G


2.018 (1,061-3,839)


rs1800532 G/T vsG/G


2.018 (1,061-3,839)


Conclusions. Our data confirmed pathogenetic link between HTR1A and TPH1 SNPs (rs6295, rs1799913, rs 800532) genotypes for the patients with diagnosis F30-39, F10 and a suicide factor.