1. ¹Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University of Munich, Munich, Germany
2. ²Department of Radiology, Ludwig-Maximilians-University of Munich, Munich, Germany

Correspondence: Dr T Frodl, Department of Psychiatry and Psychotherapy Ludwig-Maximilians-University of Munich, Nussbaumstr. 7, Munich 80336, Germany. E-mail: Thomas.Frodl@med.uni-muenchen.de

Received 19 December 2007; Revised 20 March 2008; Accepted 12 May 2008; Published online 1 July 2008.

Abstract

The serotonergic system is involved in the pathophysiology of major depression as well as in the early central nervous system development and adult neuroplasticity. The aim of the study was to examine in 77 patients with major depression and 77 healthy controls the association between the triallelic polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) and gray matter (GM) brain volumes measured with 1.5 T magnetic resonance imaging. Voxel-based morphometry were estimated on magnetic resonance images and genotyping was performed. We found that healthy controls have a strong association between the 5-HTTLPR and GM volumes of the dorsolateral prefrontal cortex, left anterior gyrus cinguli, left amygdala as well as right hippocampus, whereas there is no such association in patients with major depression. Healthy subjects carrying the S- or L_G-allele have smaller GM volumes than those with the L_A-allele, indicating that 5-HTTLPR contributes to the development of brain structures. Patients with depression show reduced GM volumes, particularly when they are homozygous for the L_A-allele, suggesting that these patients are more vulnerable for morphological changes during depressive episodes.