Carrie Breton, assistant professor of preventive medicine at The Keck School of Medicine of the University of Southern California, Los Angeles, says DNA methylation is a process that can alter a gene's usual function and these altered genes are passed along from parent to child.
The researchers observed DNA methylation-related changes in the AXL gene -- which plays a role in human cancers and in immune response -- in children exposed to maternal smoking in utero.
"We found that children exposed to maternal smoking in utero had a 2.3 percent increase in DNA methylation in AXL," Breton says in a statement. "These results confirm results from a prior study and present compelling evidence that environmental exposure to tobacco smoke during pregnancy may alter DNA methylation levels."
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