Epigenetic Regulators in Human Milk: Opportunities in ECHO with a Focus on miRNAs

Key Takeaways:*

• MiRNAs, small molecules known to regulate the expression of certain genes, represent a major class of epigenetic regulators that are abundant in human milk.
• There is growing evidence that miRNAs in maternal milk are sensitive to modifiable exposures such as environmental toxins, psychological stress, and diet. However, little is known about how these miRNAs may influence child health or the factors that influence the presence of miRNAs.
• Based on analysis of ECHO Cohort data through the New Hampshire Birth Cohort Study, researchers found that higher levels of one specific miRNA in maternal milk consumed by infants were related to a smaller body mass index (BMI) z-score for the child at age 2 years.
• A pilot study was designed to understand the potential impact of arsenic and other metals as environmental exposures to miRNA in human milk. The study found that exposure to arsenic around the time of conception and during pregnancy was related to fewer miRNAs.
• There are opportunities for ECHO researchers to analyze environmental and social stressors that may alter the composition of miRNAs in human milk. There are also gaps in knowledge about their relationship with infant health outcomes, sensitivity to stressors and health-protective behaviors, as well as the impact of pumping, reheating, or the pasteurization of human milk.

*The content presented in this webinar is the responsibility of the speaker and does not necessarily represent the official views of the National Institutes of Health.

Caitlin G. Howe, PhD

Assistant Professor of Epidemiology
Geisel School of Medicine at Dartmouth