Serotonin Transporter Polymorphism (5-HTTLPR) and Citalopram Effectiveness in Iranian Patients with Major Depressive Disorder

objective: several studies have implicated the 5-httlpr polymorphism in treatment outcomes of selective serotonin re-uptake inhibitors in patients with major depression. the aim of this study was to examine the association between polymorphism in the serotonin transporter gene and citalopram effectiveness in iranian patients suffering from major depressive disorder (mdd).methods: the sample consisted of 104 patients, with fars ethnic background, who were diagnosed according to dsm-iv-tr criteria. beck depression inventory was used to evaluate the severity of the symptoms during the follow-up, and to determine clinical response of the patients at 4th and 8th week, respectively.results: our results showed a correlation between the genotype and response to antidepressant drug citalopram, (odds ratios for l/s and l/l were 3.90 (95 percent ci: 1.29- 11.80) and 1.90 (95 percent ci: 0.72-5.08), respectively).conclusion: in conclusion, our results reveal that genetic variation of serotonin transporter is involved in clinical remission of major depressive episodes in iranian patients after citalopram treatment.