Neuroimaging genetics: new perspectives in research on major depression?
OBJECTIVE
Stress-related changes in the hippocampus are influenced by genetic factors. To enhance our understanding of both the interaction between the brain, behaviour and genetics and of biological mechanisms in mood disorders neuroimaging genetics provide a good opportunity.


METHODS
A MEDLINE search was conducted to identify articles on neuroimaging genetics in major depression (MD).


RESULTS
Hippocampal volumes were found to be associated with polymorphisms in the promotor region of the serotonin transporter (5-HTTLPR) in patients with MD. Met-allele carriers of the BDNF (val66met) polymorphism had smaller hippocampal volumes in both patients and healthy controls when compared with homozygous val-allele carriers. Polymorphisms of the serotonin transporter (5-HTTLPR) and 5-HT1a receptor are associated with increased amygdala activation investigated with functional MRI in patients with MD.


CONCLUSIONS
Genetic variants seem to modulate the effects of stress on hippocampal volumes as well as amygdala activity as well as the development of the brain.
Frodl
T
T
Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany. thomas.frodl@med.uni-muenchen.de
Möller
H-J
HJ
Meisenzahl
E
E
D000483:Alleles; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology*; D001143:Arousal / Q000235:genetics / Q000502:physiology; D001284:Atrophy; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D004644:Emotions / Q000502:physiology; D006580:Genetic Carrier Screening; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology*; D006720:Homozygote; D006801:Humans; D008279:Magnetic Resonance Imaging; D010100:Oxygen / Q000097:blood; D011110:Polymorphism, Genetic / Q000235:genetics*; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013315:Stress, Psychological / Q000150:complications
D019208:Brain-Derived Neurotrophic Factor; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D044282:Receptor, Serotonin, 5-HT1A; D010100:Oxygen