Epigenetic Mechanisms

DNA plays a central role in determining health outcomes, but as our understanding of genetic science improves, so too does our understanding of what makes us who we are as children and as adults. We now know that a child’s health outcomes are dependent on a combination of genes and the environment, as genetics alone cannot explain the full complexity of the human body, or its ailments. New research have demonstrated that identical twins with the same genetic inheritance can turn out completely different and the impact of environmental influences can be passed down through generations. The study of epigenetics therefore examines how genes are influenced and changed by outside factors instead of being solely determined by DNA.

The Center’s groundbreaking research focuses on how early exposure to environmental pollutants could alter gene expression, thereby affecting brain development, asthma, and even metabolic disorders and obesity. We believe that epigenetics might be especially important for pregnant women and infants, because much of the epigenetic code is laid down early in development; therefore, any environmental exposure that perturbs the signals controlling for gene expression while the child is developing in the womb can be potentially detrimental.  Changes in the expression of genes that are critical to neurodevelopment can lead to cognitive or behavioral deficits; they can also disable the body’s ability to control hunger or break down fat, leading to obesity and metabolic syndromes; and they can heighten inflammatory responses within the body, leading to asthma and allergy. Our recent DNA analysis of cohort 3 year olds has shown that epigenetic changes seen at birth persist through those ages.

Our newest initiatives are using state-of-the-art laboratory techniques to understand how environmental pollutants, like PAH and BPA, lead to neurodevelopmental delays, asthma, and obesity. We plan to assess whether prenatal exposure to endocrine disrupting chemicals are associated with epigenetic changes that result in these ill effects. Both endocrine disrupting chemicals BPA and PAH have been linked to obesity and metabolic syndrome in experimental and preliminary human studies, including research in our own cohort.

Although the manifestation of these health effects reflect complex interactions among many factors, the role of the environment is critical. Environmental health scientists have long established that the developing fetus is particularly vulnerable to environmental pollutants, as many substances easily penetrate the placenta. However, there is some good news: epigenetic changes do not involve changes in the primary DNA sequence, so there is the possibility to reverse them.  Thus, identification of targets for intervention is a public health priority, and our research could help identify promising opportunities to devise therapeutic treatments and improve early intervention efforts.