Genomic Analysis of Individual Differences in Ethanol Drinking: Evidence for Non-Genetic Factors in C57BL/6 Mice

Authors

Jennifer T. Wolstenholme, Virginia Commonwealth UniversityFollow
Jon A. Warner, Virginia Commonwealth University
Maria I. Capparuccini, Virginia Commonwealth UniversityFollow
Kellie J. Archer, Virginia Commonwealth UniversityFollow
Keith L. Shelton, Virginia Commonwealth UniversityFollow
Michael F. Miles, Virginia Commonwealth UniversityFollow

Document Type

Article

Original Publication Date

2011

Journal/Book/Conference Title

PLOS ONE

Volume

6

DOI of Original Publication

10.1371/journal.pone.0021100

Comments

Originally published at: http://dx.doi.org/10.1371/journal.pone.0021100

Date of Submission

November 2014

Abstract

Genetic analysis of factors affecting risk to develop excessive ethanol drinking has been extensively studied in humans and animal models for over 20 years. However, little progress has been made in determining molecular mechanisms underlying environmental or non-genetic events contributing to variation in ethanol drinking. Here, we identify persistent and substantial variation in ethanol drinking behavior within an inbred mouse strain and utilize this model to identify gene networks influencing such “non-genetic” variation in ethanol intake. C57BL/6NCrl mice showed persistent inter-individual variation of ethanol intake in a two-bottle choice paradigm over a three-week period, ranging from less than 1 g/kg to over 14 g/kg ethanol in an 18 h interval. Differences in sweet or bitter taste susceptibility or litter effects did not appreciably correlate with ethanol intake variation. Whole genome microarray expression analysis in nucleus accumbens, prefrontal cortex and ventral midbrain region of individual animals identified gene expression patterns correlated with ethanol intake. Results included several gene networks previously implicated in ethanol behaviors, such as glutamate signaling, BDNF and genes involved in synaptic vesicle function. Additionally, genes functioning in epigenetic chromatin or DNA modifications such as acetylation and/or methylation also had expression patterns correlated with ethanol intake. In verification for the significance of the expression findings, we found that a histone deacetylase inhibitor, trichostatin A, caused an increase in 2-bottle ethanol intake. Our results thus implicate specific brain regional gene networks, including chromatin modification factors, as potentially important mechanisms underlying individual variation in ethanol intake.

Rights

© 2011 Wolstenholme et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Is Part Of

VCU Pharmacology and Toxicology Publications