Serotonin Transporter Gene Promoter Hypomethylation as a Predictor of Antidepressant Treatment Response in Major Depression: A Replication Study

Abstract

Background: The serotonin transporter gene (SLC6A4; 5-HTT; SERT) is considered a prime candidate in pharmacogenetic research in major depressive disorder (MDD). Besides genetic variation, recent advances have spotlighted the involvement of epigenetic mechanisms such as DNA methylation in predicting antidepressant treatment response in "pharmaco-epigenetic"approaches. In MDD, lower SLC6A4 promoter methylation has been suggested to predict impaired response to serotonergic antidepressants. The present study sought to replicate and extend this finding in a large, independent sample of MDD patients. Methods: The sample comprised n = 236 Caucasian patients with MDD receiving antidepressant medica..