Genetic epistasis between the brain-derived neurotrophic factor Val66Met polymorphism and the 5-HTT promoter polymorphism moderates the susceptibility to depressive disorders after childhood abuse.

Abstract

BACKGROUND:

Based on biological interactions between the serotonergic system and the brain-derived neurotrophic factor (BDNF), BDNF is a plausible candidate for a gene-gene-environment interaction moderating the interaction between the s/l- promoter polymorphism of the serotonin transporter (5-HTTLPR) and childhood abuse. We tested the hypothesis of a three-way interaction with respect to depressive symptoms.

METHODS:

2035 Caucasian subjects from the Study of Health in Pomerania (German general population) completed the Beck Depression Inventory (BDI-II) and the Childhood Trauma Questionnaire. All subjects were genotyped for the BDNF Val66Met (rs6265) and the s/l 5-HTTLPR polymorphisms.

RESULTS:

Tobit regression analyses revealed a three-way-interaction between the three genotypes of 5-HTTLPR and the BDNF genotypes and overall childhood abuse for the BDI-II score (p=0.02). Emotional abuse carried the main effect of the interaction (p=0.008). The s/s genotype of the 5-HTTLPR exerted its negative impact on mental health after childhood abuse only in the presence of the BDNF Val/Val genotype but not in the presence of the BDNF Met allele. In contrast, the l allele of the 5-HTTLPR also emerged as a genetic risk factor for depression in carriers of one or two Met alleles.

CONCLUSIONS:

Our results point to a gene-gene-environment interaction that relevantly impacts on the role of the s/s genotype of the 5-HTTLPR in childhood abuse: Depending on the BDNF background (Val/Val versus Met allele) the s/s genotype showed either protective or risk properties with regard to depressive symptoms.

• Authors: Hans Jörgen Grabe, Christian Schwahn, Jessie Mahler, Katja Appel, Andrea Schulz, Carsten Spitzer, Kristin Fenske, Sven Barnow, Harald Jürgen Freyberger, Alexander Teumer, Astrid Petersmann, Reiner Biffar, Dieter Rosskopf, Ulrich John, Henry Völzke
• Journal: Progress in neuro-psychopharmacology & biological psychiatry (Prog Neuropsychopharmacol Biol Psychiatry) Vol. 36 Issue 2 Pg. 264-70 (Mar 30 2012) ISSN: 1878-4216 [Electronic] England
• PMID: 21996278 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Inc. All rights reserved.

Chemical References

• Brain-Derived Neurotrophic Factor
• SLC6A4 protein, human
• Serotonin Plasma Membrane Transport Proteins

Topics

• Adult
• Aged
• Aged, 80 and over
• Alleles
• Brain-Derived Neurotrophic Factor (genetics)
• Child
• Child Abuse (psychology)
• Depressive Disorder (complications, genetics, psychology)
• Epistasis, Genetic (genetics)
• Female
• Gene-Environment Interaction
• Genetic Predisposition to Disease (genetics)
• Genotype
• Humans
• Male
• Middle Aged
• Polymorphism, Genetic (genetics)
• Promoter Regions, Genetic (genetics)
• Psychiatric Status Rating Scales (statistics & numerical data)
• Serotonin Plasma Membrane Transport Proteins (genetics)
• Sex Characteristics
• White People (genetics)