Objective: This study was designed to test the hypothesis that serotonin-system-related genes may be correlated with suicide risk.
Method: Fifty-one unrelated Caucasian inpatients with major depression, with or without a history of suicidal acts, were genotyped for a biallelic polymorphism at the tryptophan hydroxylase locus.
Results: The less common tryptophan hydroxylase U allele occurred with greater frequency in the patients who had attempted suicide. A logistic regression analysis confirmed an association between tryptophan hydroxylase genotype and lifetime history of suicide attempts.
Conclusions: Serotonergic-system-related genes may influence the risk of suicide in persons with major depression.