Effect of prenatal exposure to phthalates on epigenome-wide DNA methylations in cord blood and implications for fetal growth: The Hokkaido Study on Environment and Children's Health

Prenatal exposure to phthalates negatively affects the offspring's health. In particular, epigenetic alterations, such as DNA methylation, may connect phthalate with health outcomes. Here, we evaluated association of di-2-ethylhexyl (DEHP) in utero cord blood epigenome-wide methylation 203 mother-child pairs enrolled Hokkaido Study on Environment and Children's Health, using Illumina HumanMethylation450 BeadChip. Epigenome-wide analysis demonstrated predominant positive associations between levels primary metabolite DEHP, mono(2-ethylhexyl) (MEHP), maternal blood. The genes annotated CpGs positively associated MEHP were enriched for pathways related metabolism, endocrine system, signal transduction. Among them, involved metabolism inversely ponderal index (PI). Further, clustering mediation analyses suggested that multiple increased changes jointly mediate DEHP PI at birth. Although further studies are required assess impact these changes, this study suggests differential link fetal growth imply has predictive value obesity.