Lack of influence of rs4680 (COMT) and rs6276 (DRD2) on diagnosis and clinical outcomes in patients with major depression

Objective. The gene coding for the catechol-O-methyltransferase (COMT) and the one coding for the dopamine receptor 2 (DRD2) have been linked with major depression (MD) and with the response to antidepressants in several studies. However, contrasting findings have been reported as well. The aim of the present study is, therefore, to investigate possible influences of rs4680 within COMT and rs6276 within DRD2, analyzed both individually and in combination, on the diagnosis and clinical outcomes in a sample of Korean MD patients treated with antidepressants. Methods. Totally, 184 Korean in-patients suffering from MD treated with either paroxetine or venlafaxine and 220 healthy control subjects were included in the present study. Depression severity was assessed by means of the Hamilton Rating Scale for Depression. Results. We were not able to find any association between the two variants under investigation and diagnosis of MD, as well as with antidepressant response. Conclusions. Although limited by several factors, including the small sample size and the impossibility to extend our findings to patients treated with different antidepressants, the results of our study provide support to the notion that these variants might not play a major role in the etiology and clinical outcomes of MD.