Cousin marriage

The NY Times writes about marriage between first cousins, which is illegal in exactly half of the 50 States of the U.S.: Shaking Off the Shame.

"But even in the United States — one of the few countries in the world where such unions are illegal — marriage between first cousins may be slowly emerging from the shadows.

Although it is still a long way from being widely accepted, in recent years cousin marriage has been drawing increased attention, as researchers study the potential health risks to children of cousins. And the couples themselves have begun to connect online, largely through a Web site called Cousincouples.com, which bills itself as “the world’s primary resource for romantic relationships among cousins,” and is trying to build support for overturning laws prohibiting cousin marriage.
For the most part, scientists studying the phenomenon worldwide are finding evidence that the risk of birth defects and mortality is less significant than previously thought. A widely disseminated study published in The Journal of Genetic Counseling in 2002 said that the risk of serious genetic defects like spina bifida and cystic fibrosis in the children of first cousins indeed exists but that it is rather small, 1.7 to 2.8 percentage points higher than for children of unrelated parents, who face a 3 to 4 percent risk — or about the equivalent of that in children of women giving birth in their early 40s. The study also said the risk of mortality for children of first cousins was 4.4 percentage points higher."
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"“It’s never as simple as people make it out to be,” said Dr. Bittles, noting that very early studies did not account for factors like access to prenatal health care, and did not distinguish between couples like Ms. Spring-Winters and her husband, the first cousins in a family to marry, and those who are part of groups in which the practice is common over generations and has led to high rates of genetic disorders. "
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"Dr. Bittles, who is working on an update of the 2002 study, and other researchers argue that laws against marriage between cousins were rooted in myth and moral objections, and that they amounted to genetic discrimination akin to eugenics or forced sterilization. People with severe disorders like Huntington’s disease, who have a 50 percent chance of passing it on to their offspring, are not barred from marrying because of the risk of genetic defects, he said, so cousins should not be, either.
Historically, marriage between cousins has been seen as desirable in many parts of the world, and even today, slightly more than 10 percent of marriages worldwide are between people who are second cousins or closer, Dr. Bittles said. In the United States, the percentage is thought to be much smaller, although it is difficult to estimate, since such marriages have long been an underground phenomenon, because of laws forbidding them and because of the lingering incest-related stigma. "
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"Martin Ottenheimer, who wrote “Forbidden Relatives: The American Myth of Cousin Marriage,” a 1996 book that was the first detailed examination of the issue in the United States, compared marriage between cousins to same-sex marriage. “People say, ‘If we permit this, what are we permitting? We’re down the slippery slope toward chaos. Then we’ll permit people to marry dogs,...’ ”
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"Despite the efforts of some in Minnesota and New Hampshire to overturn state laws against cousin marriage after the 2002 study was published, it remains illegal there. And as of 2005, it is against the law in Texas as well.
The Texas ban was part of a law targeting polygamy, and the state representative who proposed it, Harvey Hilderbran, a Republican, said he would not have introduced a bill simply to prohibit marriage between cousins. Still, he said in an interview: “Cousins don’t get married just like siblings don’t get married. And when it happens you have a bad result. It’s just not the accepted normal thing.” "