Association Study Between Brain-Derived Neurotrophic Factor Genetic Polymorphism and Treatment Responses of Selective Serotonin Reuptake Inhibitor in Major Depressive Disorder

ABSTRACT

OBJECTIVES: Recent studies suggest that brain-derived neurotrophic factor (BDNF) may play a critical role in both mechanism of antidepressant action and the pathophysiology of major depressive disorder (MDD). The aim of this study is to evaluate whether the BDNF-gene Val66Met polymorphism is associated with susceptibility of MDD, and antidepressant response in a Korean population. METHODS: To explain genetic susceptibility of MDD, we genotyped the BDNF-gene Val66Met polymorphism in 137 patients with MDD and 91 age- and sex-similar control subjects. we also examined the association of the BDNF-gene Val66Met polymorphism and therapeutic response in 137 MDD patients who received a 6-week Selective Serotonin Reuptake Inhibitor (SSRI) treatment. RESULTS: There were no significant differences in the genotype or allele frequency of the BDNF polymorphism, between the MDD and control subjects. Furthermore, no significant differences were noted in the three-genotype groups (Val/Val, Val/Met, Met/Met) between responders and non-responders. However, heterozygous patients (Val/Met) in comparison to homozygous analogs (Val/Val or Met/Met) in BDNF polymorphism tended to have more improved 6-week antidepressant response (p=0.053). In addition, higher total HAM-D-score percentage change after 6 weeks of antidepressant medication was demonstrated for the heterozygote patients in comparison to homozygous analogs (p=0.006). CONCLUSION: This finding suggests the BDNF polymorphism is associated with improved therapeutic SSRI response for patients bearing the BDNF Val/Met heterozygote in comparison to the homozygous analogs.