Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal.
CESAM - Centre for Environmental and Marine Studies, University of Aveiro, 3810-193, Aveiro, Portugal.
Biol Rev Camb Philos Soc. 2020 Jun;95(3):822-846. doi: 10.1111/brv.12589. Epub 2020 Feb 11.
Epigenetic mechanisms have gained relevance in human health and environmental studies, due to their pivotal role in disease, gene × environment interactions and adaptation to environmental change and/or contamination. Epigenetic mechanisms are highly responsive to external stimuli and a wide range of chemicals has been shown to determine specific epigenetic patterns in several organisms. Furthermore, the mitotic/meiotic inheritance of such epigenetic marks as well as the resulting changes in gene expression and cell/organismal phenotypes has now been demonstrated. Therefore, epigenetic signatures are interesting candidates for linking environmental exposures to disease as well as informing on past exposures to stressors. Accordingly, epigenetic biomarkers could be useful tools in both prospective and retrospective risk assessment but epigenetic endpoints are currently not yet incorporated into risk assessments. Achieving a better understanding on this apparent impasse, as well as identifying routes to promote the application of epigenetic biomarkers within environmental risk assessment frameworks are the objectives of this review. We first compile evidence from human health studies supporting the use of epigenetic exposure-associated changes as reliable biomarkers of exposure. Then, specifically focusing on environmental science, we examine the potential and challenges of developing epigenetic biomarkers for environmental fields, and discuss useful organisms and appropriate sequencing techniques to foster their development in this context. Finally, we discuss the practical incorporation of epigenetic biomarkers in the environmental risk assessment of chemicals, highlighting critical data gaps and making key recommendations for future research within a regulatory context.
表观遗传机制在人类健康和环境研究中变得越来越重要，因为它们在疾病、基因与环境相互作用以及适应环境变化和/或污染方面起着关键作用。表观遗传机制对外界刺激高度敏感，大量化学物质已被证明能在几种生物体中确定特定的表观遗传模式。此外，这种表观遗传标记的有丝分裂/减数分裂遗传以及由此导致的基因表达和细胞/生物体表型的变化已经得到证实。因此，表观遗传特征是将环境暴露与疾病联系起来以及提供过去暴露于应激源信息的有趣候选者。因此，表观遗传生物标志物可作为前瞻性和回顾性风险评估的有用工具，但目前尚未将表观遗传终点纳入风险评估中。本综述的目的是更好地了解这一明显的僵局，并确定促进在环境风险评估框架内应用表观遗传生物标志物的途径。我们首先从支持将表观遗传暴露相关变化用作可靠暴露生物标志物的人类健康研究中收集证据。然后，特别关注环境科学，我们研究了为环境领域开发表观遗传生物标志物的潜力和挑战，并讨论了在这方面促进其发展的有用生物体和适当的测序技术。最后，我们讨论了在化学物质的环境风险评估中实际纳入表观遗传生物标志物的问题，突出了关键数据差距，并在监管背景下为未来的研究提出了关键建议。
