Environmental influences on epigenetic profiles

Abstract

Studies of environmental challenges, such as hazardous air pollutants, nonmutagenic toxins, diet choice, and maternal behavioral patterns, reveal changes in gene expression patterns, DNA methylation, and histone modifications that are in causal association with exogenous exposures. In this article we summarize some of the recent advances in the field of environmental epigenetics and highlight seminal studies that implicate in utero exposures as causative agents in altering not only the epigenome of the exposed gestation, but that of subsequent generations. Current studies of the effects of maternal behavior, exposure to environmental toxins, and exposure to maternal diet and an altered gestational milieu are summarized.

Figure 1

Behavioral influences, such as fear and depression, cause specific epigenetic changes. BDNF, brain-derived neurotrophic factor; CpG, cytosine followed by a guanine; ERα, α subunit of the estrogen receptor; GR, glucocorticoid receptor.

Figure 2

Exposure to environmental toxins alters DNA methylation and histone modification profiles. CpG, cytosine followed by a guanine.

Figure 3

Maternal diet can cause in utero epigenetic changes in the fetus thought to reprogram genes and increase the susceptibility to adult disease. CpG, cytosine followed by a guanine; IGF, HDAC, histone deacetylase.