Environmental chemicals and DNA methylation in adults: a systematic review of the epidemiologic evidence

Clinical Epigenetics

Maria Tellez-Plaza⁴  Ana Navas-Acien⁷  Jose M Ordovas⁵  Josep Redon¹  Wan-Yee Tang⁴  Pilar Rentero-Garrido²  Chin-Chi Kuo⁶  Adrian Ruiz-Hernandez³ 

[1] CIBER Physiopathology of Obesity and Nutrition (CIBEROBN), Institute of Health Carlos III, Minister of Health, Madrid, Spain;Genotyping and Genetic Diagnosis Unit, Institute for Biomedical Research INCLIVA, Av. Menendez Pelayo, 4 Accesorio, Valencia, 46010, Spain;Area of Cardiometabolic and Renal Risk, Institute for Biomedical Research Hospital Clinic de Valencia INCLIVA, Av. Menendez Pelayo 4, Accesorio, Valencia, 46010, Spain;Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore 21205, MD, USA;Instituto Madrileño de Estudios Avanzados en Alimentación, Ctra. de Cantoblanco 8, Madrid, 28049, Spain;Department of Internal Medicine, Kidney Institute and Division of Nephrology, China Medical University Hospital and College of Medicine, China Medical University, 2 Yude Road, Taichung 40447, Taiwan;Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore 21205, MD, USA

关键词: Polycyclic aromatic hydrocarbons;    Bisphenol A;    Persistent organic pollutants;    Metals;    Mercury;    Lead;    Cadmium;    Environmental chemicals;    DNA methylation;    Systematic review;   

Others  :  1210205
DOI  :  10.1186/s13148-015-0055-7

 received in 2014-11-05, accepted in 2015-02-09,  发布年份 2015

【 摘 要 】

Current evidence supports the notion that environmental exposures are associated with DNA-methylation and expression changes that can impact human health. Our objective was to conduct a systematic review of epidemiologic studies evaluating the association between environmental chemicals with DNA methylation levels in adults. After excluding arsenic, recently evaluated in a systematic review, we identified a total of 17 articles (6 on cadmium, 4 on lead, 2 on mercury, 1 on nickel, 1 on antimony, 1 on tungsten, 5 on persistent organic pollutants and perfluorinated compounds, 1 on bisphenol A, and 3 on polycyclic aromatic hydrocarbons). The selected articles reported quantitative methods to determine DNA methylation including immunocolorimetric assays for total content of genomic DNA methylation, and microarray technologies, methylation-specific quantitative PCR, Luminometric Methylation Assay (LUMA), and bisulfite pyrosequencing for DNA methylation content of genomic sites such as gene promoters, LINE-1, Alu elements, and others. Considering consistency, temporality, strength, dose-response relationship, and biological plausibility, we concluded that the current evidence is not sufficient to provide inference because differences across studies and limited samples sizes make it difficult to compare across studies and to evaluate sources of heterogeneity. Important questions for future research include the need for larger and longitudinal studies, the validation of findings, and the systematic evaluation of the dose-response relationships. Future studies should also consider the evaluation of epigenetic marks recently in the research spotlight such as DNA hydroxymethylation and the role of underlying genetic variants.

【 授权许可】

   
2015 Ruiz-Hernandez et al.; licensee BioMed Central.

【 图 表 】

Figure 1.

Figure 2.

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