Edwin Van Wijngaarden, Ph.D.
University of Rochester
P30ES001247, R01ES010219, R03ES027514
Mothers with certain genetic variations may have different levels of mercury in their hair and their children may have different early neurodevelopmental outcomes, according to an NIEHS-funded study. The researchers focused on how a mother’s genetic differences could influence her levels of mercury and the levels in her children. They also looked at associations between these levels and early life development.
The researchers studied 1,449 mothers in Seychelles who eat a diet rich in fish, which is the main source of low-level mercury exposure in people. They examined associations among mercury levels in maternal hair and blood, mercury in fetal cord blood, and mental and motor development during childhood. They also examined maternal genetic differences, focusing on glutathione (GSH) pathways, which play a key role in the metabolism and elimination of mercury.
They showed that some maternal GSH-related genes were associated with higher levels of mercury concentrations in the mothers’ hair but not in maternal or fetal blood. One maternal genetic difference was also linked to lower mental development among children. The researchers observed that certain GSH-related gene variations in the mother modified the associations between increased mercury levels in hair and blood and mental and motor development in the child.
According to the authors, the results indicate that maternal genetic variation in GSH-related genes potentially influence maternal mercury metabolism, which may affect associations between mercury exposure and developmental outcomes. The findings provide evidence that health impacts of a fish-rich diet during pregnancy may differ among individuals within a population.
Citation: Wahlberg K, Love TM, Pineda D, Engstrom K, Watson GE, Thurston SW, Yeates AJ, Mulhern MS, McSorley EM, Strain JJ, Smith TH, Davidson PW, Shamlaye CF, Myers GJ, Rand MD, van Wijngaarden E, Broberg K. 2018. Maternal polymorphisms in glutathione-related genes are associated with maternal mercury concentrations and early child neurodevelopment in a population with a fish-rich diet. Environ Int 115:142–149.