Brain derived neurotrophic factor gene polymorphism (Val66Met) and short-term antidepressant response in major depressive disorder

Backgrounds: To determine the association between the brain derived neurotrophic factor (BDNF) Val66Met polymorphism and short-term antidepressant response in Taiwanese patients with major depressive disorder (MDD). Methods: We recruited 117 MDD patients who were randomized to fluoxetine or venlafaxine treatment and 106 controls. The association between genotypes and percentage changes in the Hamilton Rating Scale for Depression (HAM-D) scores over time was analyzed by repeated-measures ANOVA. The antidepressants were included in the model as covariates. Results: The frequency of the BDNF Val66Met polymorphisms was not significantly different between patient and control groups. Significantly changes in HAM-D scores were noted after 2 and 4 weeks of venlafaxine treatment among different genotypes. Conclusions: Results suggest antidepressants acting through different mechanisms may affect the BDNF Val66Met polymorphism differently.