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Journal of Neuroinflammation
Published in: Journal of Neuroinflammation 1/2012

Open Access 01-12-2012 | Research

Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain

Authors: Bernhard T Baune, Carsten Konrad, Dominik Grotegerd, Thomas Suslow, Eva Birosova, Patricia Ohrmann, Jochen Bauer, Volker Arolt, Walter Heindel, Katharina Domschke, Sonja Schöning, Astrid V Rauch, Christina Uhlmann, Harald Kugel, Udo Dannlowski

Published in: Journal of Neuroinflammation | Issue 1/2012

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Abstract

Background

Cytokines such as interleukin 6 (IL-6) have been implicated in dual functions in neuropsychiatric disorders. Little is known about the genetic predisposition to neurodegenerative and neuroproliferative properties of cytokine genes. In this study the potential dual role of several IL-6 polymorphisms in brain morphology is investigated.

Methodology

In a large sample of healthy individuals (N = 303), associations between genetic variants of IL-6 (rs1800795; rs1800796, rs2069833, rs2069840) and brain volume (gray matter volume) were analyzed using voxel-based morphometry (VBM). Selection of single nucleotide polymorphisms (SNPs) followed a tagging SNP approach (e.g., Stampa algorigthm), yielding a capture 97.08% of the variation in the IL-6 gene using four tagging SNPs.
Principal findings/results
In a whole-brain analysis, the polymorphism rs1800795 (−174 C/G) showed a strong main effect of genotype (43 CC vs. 150 CG vs. 100 GG; x = 24, y = −10, z = −15; F(2,286) = 8.54, puncorrected = 0.0002; pAlphaSim-corrected = 0.002; cluster size k = 577) within the right hippocampus head. Homozygous carriers of the G-allele had significantly larger hippocampus gray matter volumes compared to heterozygous subjects. None of the other investigated SNPs showed a significant association with grey matter volume in whole-brain analyses.

Conclusions/significance

These findings suggest a possible neuroprotective role of the G-allele of the SNP rs1800795 on hippocampal volumes. Studies on the role of this SNP in psychiatric populations and especially in those with an affected hippocampus (e.g., by maltreatment, stress) are warranted.
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Metadata
Title
Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain
Authors
Bernhard T Baune
Carsten Konrad
Dominik Grotegerd
Thomas Suslow
Eva Birosova
Patricia Ohrmann
Jochen Bauer
Volker Arolt
Walter Heindel
Katharina Domschke
Sonja Schöning
Astrid V Rauch
Christina Uhlmann
Harald Kugel
Udo Dannlowski
Publication date
01-12-2012
Publisher
BioMed Central
Published in
Journal of Neuroinflammation / Issue 1/2012
Electronic ISSN: 1742-2094
DOI
https://doi.org/10.1186/1742-2094-9-125

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