Concordance in hippocampal and fecal Nr3c1 methylation is moderated by maternal behavior in the mouse
Article first published online: 8 NOV 2012
© 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 2, Issue 12, pages 3123–3131, December 2012
How to Cite
Ecology and Evolution 2012; 2(12): 3123–3122
- Issue published online: 13 DEC 2012
- Article first published online: 8 NOV 2012
- Manuscript Accepted: 3 OCT 2012
- Manuscript Revised: 25 SEP 2012
- Manuscript Received: 9 AUG 2012
- National Institutes of Health. Grant Number: DP2OD001674
- University of Michigan NIEHS P30 Core Center. Grant Number: ES017885
- DNA methylation;
- fecal samples;
- glucocorticoid receptor;
- maternal behavior;
Recent advances in genomic technologies now enable a reunion of molecular and evolutionary biology. Researchers investigating naturally living animal populations are thus increasingly able to capitalize upon genomic technologies to connect molecular findings with multiple levels of biological organization. Using this vertical approach in the laboratory, epigenetic gene regulation has emerged as an important mechanism integrating genotype and phenotype. To connect phenotype to population fitness, however, this same vertical approach must now be applied to naturally living populations. A major obstacle to studying epigenetics in noninvasive samples is tissue specificity of epigenetic marks. Here, using the mouse as a proof-of-principle model, we present the first known attempt to validate an epigenetic assay for use in noninvasive samples. Specifically, we compare DNA methylation of the NGFI-A (nerve growth factor-inducible protein A) binding site in the promoter of the glucocorticoid receptor (Nr3c1) gene between central (hippocampal) and peripheral noninvasive (fecal) tissues in juvenile Balb/c mice that had received varying levels of postnatal maternal care. Our results indicate that while hippocampal DNA methylation profiles correspond to maternal behavior, fecal DNA methylation levels do not. Moreover, concordance in methylation levels between these tissues within individuals only emerges after accounting for the effects of postnatal maternal care. Thus, although these findings may be specific to the Nr3c1 gene, we urge caution when interpreting DNA methylation patterns from noninvasive tissues, and offer suggestions for further research in this field.