Lack of association between endothelial nitric oxide synthase (NOS3) gene polymorphisms and suicide attempts

OBJECTIVE: The aim of this study is to investigate the association between two polymorphisms of endothelial nitric oxide synthase (NOS3) and suicide attempts. METHODS: We genotyped 186 suicide attempters and 420 unrelated healthy controls. The following polymorphisms were analysed: T-786C and 27-bp repeat in intron 4. RESULTS: No significant differences were found in genotype or in allelic distribution of the aforesaid polymorphisms. There were also no differences in the genotype distribution or allelic frequencies when separately assessing males and females or impulsive and non-impulsive attempters and normal controls. Estimated haplotype frequencies were similar in both groups. CONCLUSION: Our data do not support the hypothesis that genetically determined changes in the NOS3 gene confer increased susceptibility for suicidal behavior.