Grant looked for mutations in the gene known as GPA in red blood cells collected from the cord blood of babies born to mothers exposed to smoke. The results are in agreement with previous studies that analyzed white blood cells from newborn cord blood for mutations in HPRT, a different gene commonly used as a biomarker for exposure to carcinogens. Those studies also documented a correlation between maternal exposure to both primary and second-hand smoke and increases in the frequency of HPRT mutations.
"By using a different assay, we were able to pick up a completely distinct yet equally important type of genetic mutation that is likely to persist throughout a child's lifetime," Grant said. He concluded that the assays for mutations in either gene should be considered complementary tests, reflecting mutations that occur through different mechanisms.
"Pregnant women should not only stop smoking, but be aware of their exposure to tobacco smoke from other family members, work and social situations," Grant said.
