Doctors have identified a gene linked to an increased risk of premature birth among black women
The discovery is likely to be controversial, as are many scientific studies drawing connections between genetics, race and disease.
The underlying issue is enormously significant: Rates of pre-term births among black women are two to three times higher than they are for white women.
For years, scientists have wondered about the role of genetics, in addition to environmental factors such as smoking or socioeconomic factors such as poverty.
Now, they have found evidence that genetics, indeed, appears to be related.
At issue is a variation in a gene that directs the production of collagen, a key component of the amniotic sac that lines a pregnant woman's uterus. The sac holds the fluid that cushions a baby inside the uterus.
Women with the variant gene are more prone to experience a rupture of the sac.
This "premature rupture of membranes" is responsible for about 40 percent of premature births in the United States, more than any other cause, said Dr. Roberto Romero, chief of the perinatology research branch at the National Institute of Child Health & Human Development.
The ruptures are more common among black women, as is the variant gene, according to the new study, reported online Monday by the Proceedings of the National Academy of Science.
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