Korean Journal of Biological Psychiatry

The pharmacotherapy of depression has reduced morbidity and improved outcome for many depressive patients. A wide range of classical and new antidepressants are available for their treatment. However, 30-40% of all patients do not respond sufficiently to the initial treatment and present adverse effects. Pharmacogenetics studies the genetic basis of an individual's ability to respond to pharmacotherapy. Recently, some reports on serotonin transporter gene polymorphisms and their influence on the response to antidepressive therapy provide an interesting diagnostic tool in assessing the chances of response to antidepressants. We also investigated the relationship between serotonin transprter polymorphisms(5-HTTLPR) and the long-term effect of the antidepressant treatment. 128 depressive patients were enrolled into 2nd year study. The therapeutic response of each subset was not different at 8th, 16th week, but the subset with homozygote(l/l) of long variant showed a better therapeutic response to antidepressant than the heterozygote(l/s) of long and short variant, which showed a better therapeutic response than the subset with homozygote(s/s) of short variant at 1st year and 2nd year after the antidepressant treatment. This result shows that the serotonin transporter polymorphisms may be related to the long-term effect of antidepressant treatment. The potential for pharmacogenomics, the use of genetic information to guide pharmacotherapy and improve outcome by providing individualized treatment decisions, has gained increasing attention. pharmacogenomics will contribute to individualize drug choice by using genotype to predict positive clinical outcomes, adverse reactions, and levels of drug metabolism. Personalized medicine, the use of marker-assisted diagnosis and targeted therapies derived from an individual molecular profile, will impact the antidepressant therapy and this approach will replace the traditional trial-and-error practice of medicine.

Keywords Depression;Pharmacogenomics;Antidepressant.