The functional val108/158met polymorphism of the COMT gene (rs4680) was evaluated in major depressive disorder (MDD), and in the treatment response to antidepressants in MDD. We could not demonstrate any significant difference in the distribution of this COMT single-nucleotide polymorphism (SNP) in the treatment response to selective serotonin reuptake inhibitors or between patients with MDD and control subjects.
The role of a functional polymorphism in the transcriptional control region of serotonin transporter gene (5-HTTLPR, SERTPR) has been studied intensively in major depression and in the response to selective serotonin inhibitors (SSRIs) in major depression. The findings have been contradictory, although majority of the studies indicate that the short allele is associated with poor response to SSRIs in major depression. In the present study, we evaluated the association of 5-HTTLPR with treatment response to SSRI medication in Finnish Caucasian MDD patients. A secondary purpose was to study the possible association of this particular polymorphism with major depressive disorder. The aim of the study was to replicate the previous findings in this area. Primary outcomes of the treatment were remission, defined by an exit score of seven or less, and response, defined by a reduction of at least 50% on the MADRS. We had also a control population of 375 healthy blood donors, as a secondary objective was to evaluate the possible association of this particular polymorphism with major depressive disorder. Twenty-nine of the 85 (34.1%) patients reached the remission and 58.8% achieved the predefined response criteria. The l/l genotype of 5-HTTLPR was presented in 51.7% of those patients who achieved remission vs. 25.0% in the non-remitters (P = 0.03). The result remained statistically significant after adjusting for age, gender, medication and MADRS points at the study entry. However, the small sample size limits the reliability of this result.
Brain-derived neurotrophic factor (BDNF) is suggested to play a role in the aetiology of major depression and in the antidepressant response in patients with major depression. Several BDNF gene polymorphisms have been investigated in the above-mentioned context. The aim of the present study was to examine the role of two BDNF gene polymorphisms (rs11030101 and rs61888800) in relation to the response to selective serotonin reuptake inhibitor medication in 106 patients of Finnish origin suffering from major depression. The secondary objective was to evaluate the association of these two BDNF polymorphisms in major depression, as we also had a control population of 386 healthy individuals. We did not find any significant differences in the distribution of these two BDNF gene polymorphisms in our patient population in relation to remission or response to treatment with selective serotonin reuptake inhibitor. Also, there were no significant differences between the patients and the controls.