Changes in DNA Methylation Induced by Dioxins and Dioxin-Like Compounds as Potential Predictor of Disease Risk

Dioxins and dioxin-like compounds are persistent organic pollutants (POPs) and technogenic ecotoxicants, the most dangerous of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). A peculiar feature of the considered genotoxicants that distinguishes them from other POPs is hormone-like activity, which is realized through binding to a special cellular protein, the Aryl hydrocarbon Receptor (AhR). In the present study, the phenomenological aspects of DNA methylation changes induced by dioxins and dioxin-like compounds and revealed in the studies in vitro and in vivo are considered. In animal models, multigenerational and transgenerational effects of dioxin-induced locus-specific DNA methylation changes and their association with reproductive dysfunctions and congenital malformations were firmly established. The importance of investigations of the long-term epigenetic consequences of human exposure to dioxins and the potential value of such studies for preventive diagnostics of somatic and reproductive pathologies are discussed.