title: Environmental Deflection: The Impact of Toxicant Exposures on the Aging Epigenome.
abstract: Epigenetic drift and age-related methylation have both been used in the literature to describe changes in DNA methylation that occurs with aging. However, ambiguity remains regarding the exact definition of both of these terms, and neither of these fields of study explicitly considers the impact of environmental factors on the aging epigenome. Recent twin studies have demonstrated longitudinal, pair-specific discordance in DNA methylation patterns, suggesting an effect of the environment on age-related methylation and/or epigenetic drift. Supporting this idea, other new reports have shown clear environment- and toxicant-mediated shifts away from the baseline rates of age-related methylation and epigenetic drift within an organism, a process we now term "environmental deflection." By defining and delineating environmental deflection, this contemporary review aims to highlight the effects of specific toxicological factors on the rate of DNA methylation changes that occur over the life course. In an effort to inform future epigenetics-based toxicology studies, a field of research now classified as toxicoepigenetics, we provide clear definitions and examples of "epigenetic drift" and "age-related methylation," summarize the recent evidence for environmental deflection of the aging epigenome, and discuss the potential functional effects of environmental deflection.
authors.affiliation: Environmental Health Sciences.
authors.forename: Joseph
authors.initials: J
authors.lastname: Kochmanski
authors.affiliation: Environmental Health Sciences.
authors.forename: Luke
authors.initials: L
authors.lastname: Montrose
authors.affiliation: Environmental Health Sciences.
authors.forename: Jaclyn M
authors.initials: JM
authors.lastname: Goodrich
authors.affiliation: Environmental Health Sciences.|Nutritional Sciences, School of Public Health, University of Michigan, Washington Heights, Ann Arbor, Michigan 48109.
authors.forename: Dana C
authors.initials: DC
authors.lastname: Dolinoy
mesh_terms: D000375:Aging / Q000235:genetics*; D000818:Animals; D004781:Environmental Exposure / Q000009:adverse effects*; D004785:Environmental Pollutants / Q000633:toxicity*; D044127:Epigenesis, Genetic / Q000187:drug effects*; D005260:Female; D006801:Humans; D010641:Phenotype; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000235:genetics
chemical_list: D004785:Environmental Pollutants
keywords: (Reproductive & Developmental Toxicology; aging); developmental toxicity); environmental (Environmental Toxicology; exposure; post-natal (Reproductive & Developmental Toxicology).; prenatal (Reproductive & Developmental Toxicology