The Biological Embedding of Early Life Socioeconomic and Family Adversity in Children’s Genome-wide DNA Methylation. Homo sapiens

Early life social experiences are believed to confer persistent effects on individual’s biology and subsequent functioning and health. Using a diverse, longitudinal community sample of 178 children, we show that three different types of early life social experience: family income, parental education, and family psychosocial adversity, each predict DNA methylation within buccal epithelial cells. Each predictor was significantly associated with DNA methylation within a unique set of genomic CpG sites, with income showing the greatest number of associations. Findings were independently verified using pyrosequencing. Our results provide evidence for longitudinal associations between early life social environment and variation in DNA methylation during childhood, after adjusting for genetic ancestry and self-reported ethnic minority status. Gene ontology analyses of top, differentially methylated CpG sites point to genes serving immune and developmental regulation functions, suggesting potential pathways for the biological embedding of early life stress and its association with later development and health. Overall design: This cohort consist of genomic DNA extracted from 178 buccal swabs, bisulphite converted and hybridized to the Illumina Infinium HumanMethylation450 Beadchip for genome wide DNA methylation profiling.