The researchers looked at blood samples of newborns, mainly from the umbilical cord, and compared these to samples from babies that have not been exposed to their mothers’ smoking during pregnancy. The researchers found over 6,000 spots where the DNA had been modified.
Nearly half of those locations could be linked to a specific gene that is involved in the lung and nervous system development, birth defects, and smoking-related cancers. Additionally, many of those DNA changes were still found in older children whose mothers smoked during pregnancy.
Co-senior author Stephanie London said in the new release, “I find it kind of amazing when we see these epigenetic signals in newborns, from in utero exposure, lighting up the same genes as an adult’s own cigarette smoking. There’s a lot of overlap. This is a blood-borne exposure to smoking — the fetus isn’t breathing it, but many of the same things are going to be passing through the placenta.”