July 27, 2005


Even dad's smoke bad for fetuses (Anita Srikameswaran, July 27, 2005, Pittsburgh Post-Gazette)

Pooling data from three earlier studies, Stephen G. Grant, an environmental and occupational health researcher at the University of Pittsburgh's Graduate School of Public Health, found that secondhand smoke leads to the same number of genetic mutations in newborns as does smoking by the mother herself.

As Grant put it: "Passive exposure gives you just as much of an exposure and just as bad damage as active smoking." [...]

In the earlier studies, umbilical cord blood samples from newborns were tested for changes in the HPRT gene, which is on the X, or female, chromosome.

The study compared gene mutation rates among babies born to mothers who smoked, quit smoking when they learned they were pregnant, lived or worked with smokers, or had no exposure to smoking.

"What we found is the three exposed groups were all pretty much the same," Grant said. "But they were all significantly different from the unexposed."

Mutations of the HPRT gene were almost twice as common in the exposed groups, he said.

"If the mutations are occurring at this gene, there's no reason why they shouldn't be occurring at the same elevated frequencies at other genes," Grant said. Depending on which genes are affected, those changes could ultimately lead to birth defects, cancer or other conditions.

And to evolution.

Posted by Orrin Judd at July 27, 2005 12:00 AM

Metastudies are always wrong or, to be more precise, metastudies never surprise their designers.

Posted by: David Cohen at July 27, 2005 10:35 AM

Ionizing radiation can definitely cause mutations but there aren't any three-eyed mutants walking around Hiroshima.

It's beginning to look like human beings are anomalously resistant to mutations.

Posted by: Joseph Hertzlinger at July 27, 2005 1:24 PM