Dataset Information

Prenatal Exposure to Mercury: Associations with Global DNA Methylation and Hydroxymethylation in Cord Blood and in Childhood.

ABSTRACT:

Background

Mercury is a global pollutant, and prenatal exposure is associated with adverse health effects. To date, no studies have evaluated the association between prenatal mercury exposure and DNA hydroxymethylation, an epigenetic modification important for tissue differentiation and embryonic development.

Objectives

We sought to evaluate the association between prenatal mercury exposure and offspring global DNA methylation and hydroxymethylation at birth and test for persistence of the association in childhood.

Methods

Within Project Viva, a U.S. prebirth cohort, we examined associations of maternal second trimester red blood cell mercury (RBC-Hg) concentrations with global 5-hydroxymethylcytosine (%-5hmC) and 5-methylcytosine (%-5mC) DNA content in blood collected at birth (n=306), early childhood (n=68; 2.9 to 4.9 y), and midchildhood (n=260; 6.7 to 10.5 y).

Results

Median prenatal RBC-Hg concentration was 3.23?g/g [interquartile?range?(IQR)=3.29]. At birth, median cord blood %-5mC, %-5hmC, and their ratio were 4.95%, 0.22%, and 24.37, respectively. The mean adjusted difference [95% confidence interval (CI)] of blood %-5hmC for a doubling in prenatal RBC-Hg concentration was -0.013% (-0.029, 0.002), -0.031% (-0.056, -0.006), and 0.005% (-0.007, 0.018) at birth, early, and midchildhood, respectively. The corresponding relative adjusted change in the genomic ratio of %-5mC to %-5hmC for a doubling in prenatal RBC-Hg concentration was 4.70% (0.04, 9.58), 22.42% (7.73, 39.11), and 0.73% (-4.18, 5.88) at birth, early, and midchildhood, respectively. No associations were present between prenatal maternal RBC-Hg and %-5mC at any time point.

Conclusions

Prenatal mercury exposure was associated with lower %-5hmC genomic content and a corresponding increase in the ratio of %-5mC to %-5hmC in cord blood. This association was persistent in early but not midchildhood blood. Our results demonstrate the potential malleability of epigenetic modifications associated with mercury exposure in utero. https://doi.org/10.1289/EHP1467.

SUBMITTER: Cardenas A

PROVIDER: S-EPMC5783674 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Publications

Prenatal Exposure to Mercury: Associations with Global DNA Methylation and Hydroxymethylation in Cord Blood and in Childhood.

Cardenas Andres A Rifas-Shiman Sheryl L SL Godderis Lode L Duca Radu-Corneliu RC Navas-Acien Ana A Litonjua Augusto A AA DeMeo Dawn L DL Brennan Kasey J KJ Amarasiriwardena Chitra J CJ Hivert Marie-France MF Gillman Matthew W MW Oken Emily E Baccarelli Andrea A AA

Environmental health perspectives 20170829 8

<h4>Background</h4>Mercury is a global pollutant, and prenatal exposure is associated with adverse health effects. To date, no studies have evaluated the association between prenatal mercury exposure and DNA hydroxymethylation, an epigenetic modification important for tissue differentiation and embryonic development.<h4>Objectives</h4>We sought to evaluate the association between prenatal mercury exposure and offspring global DNA methylation and hydroxymethylation at birth and test for persisten ...[more]

PMID: 28934725

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Dataset Information

Prenatal Exposure to Mercury: Associations with Global DNA Methylation and Hydroxymethylation in Cord Blood and in Childhood.

Background

Objectives

Methods

Results

Conclusions

Publications

Prenatal Exposure to Mercury: Associations with Global DNA Methylation and Hydroxymethylation in Cord Blood and in Childhood.

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