A study finds links among the nutritional, microbial, and psychosocial characteristics of childhood environment and levels of methylation (DNAm) of inflammatory genes in adulthood. Inflammation contributes to a wide range of human diseases, and previous studies have found that the environment during infancy and childhood can influence inflammation in adulthood. The underlying biological mechanisms linking early environmental factors with adult inflammation are unknown. To test whether epigenetic processes contribute to the observed link, Thomas McDade and colleagues obtained blood samples from 494 participants, ages 20-22, in a longitudinal study in Cebu, Philippines. The microbial, nutritional, and socioeconomic characteristics of the participants’ childhood environments varied widely. The authors analyzed 114 target genes involved in inflammation regulation, and found 10 methylated sites across nine genes, where the level of DNAm was tied to one of the following childhood environmental factors: household socioeconomic status, long parental absence, infant exposure to animal feces, birth during the dry season, and breastfeeding duration. The authors identified four genes where the level of DNAm was associated with inflammatory biomarkers from blood plasma, suggesting that the level of DNAm at these sites may be functionally relevant. According to the authors, DNAm is a potentially important biological mechanism through which childhood environments may influence adult inflammation.
Article #16-20661: “Social and physical environments early in development predict DNA methylation of inflammatory genes in young adulthood,” by Thomas W. McDade et al.