If a pregnant woman is exposed to lead, it can pass through the placenta into the baby's developing bones and other organs. Previous research has suggested that exposure to heavy metal toxicants can influence a person's global DNA methylation profile. A new study has revealed that mothers with high levels of lead in their blood not only affect the fetal cells of their unborn children, but also their grandchildren.
Pregnant women with a past exposure to lead can affect the unborn child's brain, causing developmental problems later in life. The current study revealed that lead exposure can cause specific changes in DNA methylation, which can be detected in dried blood spots beyond one generation.
Lead researcher Douglas Ruden from Wayne State University said, "Our results suggest lead exposure during pregnancy affects the DNA methylation status of the fetal germ cells, which leads to altered DNA methylation in grandchildren's neonatal dried blood spots."
The researchers stated that this novel, two-generational study design might be able to identify the genes that may serve as possible candidate biomarkers for future transgenerational risk assessment studies. Ruden added, "However, the altered DNA methylation profiles of the grandchildren's blood are apparently normalized during postnatal development."
The study appeared online in the Scientific Reports.