Environmental Lead Exposure in Early Childhood Alters Imprinted Gene Regulation
Press Reports: North Carolina State University,
15 July 2015: Although lead (Pb) is a neurotoxin, the mechanism by which it effects neurodevelopment, and the acceptable threshold of exposure to the developing child are still unclear. Imprinted genes have one parental allele silenced epigenetically, and they play critical roles in human development (Jirtle and Weidman 2007). In a recent study published in Environmental Health Perspectives, Cathrine Hoyo and her colleagues at North Carolina State University demonstrated, with the use of participants in the Cincinnati Lead Study, that children exposed early in development to high levels of Pb have altered DNA methylation in the regulatory elements of imprinted genes - PEG3, H19/IGF2 and PLAGL1/HYMAI - over three decades after exposure. It remains unknown whether the Pb exposure previously associated with decreased gray matter volume (Cecil et al. 2008) and delinquent behavior (Dietrich et al. 2001) in this study population is mediated by the epigenetic dysregulation of these imprinted genes.