Cheyenne
Ms. Smarty Pantsless
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- Apr 18, 2000
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Being more than kissing cousins OK
Fears of passing defects to offspring overblown, research finds
Denise Grady, New York Times
Thursday, April 4, 2002
©2002 San Francisco Chronicle
URL:
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2002/04/04/MN91383.DTL
Contrary to widely held beliefs and long-standing taboos in America, first cousins can have children together without a great risk of birth defects or genetic disease, scientists are reporting today. They say there is no biological reason to discourage cousins from marrying.
First cousins are somewhat more likely than unrelated parents to have a child with a serious birth defect, mental retardation or genetic disease, but their increased risk is nowhere near as large as most people think, the scientists said.
In the general population, the risk that a child will be born with a problem such as spina bifida or cystic fibrosis is 3 to 4 percent; to that background risk, first cousins must add 1.7 to 2.8 percentage points, the researchers said.
Although the increase represents a near doubling of the risk, the result is still not considered large enough to discourage people from having children, said Dr. Arno Motulsky, a professor emeritus of medicine at the University of Washington and the senior author of the report.
"In terms of general risks in life, it's not very high," Motulsky said.
The report is being published today in the Journal of Genetic Counseling.
The researchers, a panel convened by the National Society of Genetic Counselors, based their conclusions on a review of six major studies conducted from 1965 to August 2000, involving many thousands of births.
Motulsky said medical geneticists had known for a long time that there was little or no harm in cousins marrying and having children. "Somehow, this hasn't become general knowledge," he said, even among doctors.
California is among the states that allow cousins to marry. But 24 states have laws forbidding marriage for first cousins and seven have limits like requiring genetic counseling. No countries in Europe have such prohibitions, and in parts of the Middle East, Africa and Asia, marriages between cousins are considered preferable.
Motulsky said many immigrants from cultures where cousin marriages are common are expected to continue the tradition in America, and doctors and genetic counselors should respect their wishes. He said the American laws against cousin marriage should be abolished.
Motulsky said researchers did not know why marriage between cousins was viewed with such distaste in America, although he said some of the revulsion may have stemmed from the eugenics movement that flourished here early in the 20th century.
It is not known how many cousins marry or live together. Estimates of marriages between related people, which include first cousins and more distant ones, range from less than 0.1 percent of the general population to 1.5 percent. In the past, small studies have found much higher rates in some areas:
A survey in 1942 found 18.7 percent in a small town in Kentucky, and a 1980 study found 33 percent in a Mennonite community in Kansas.
The report made a point of saying that the term "incest" should not be applied to cousins but only to sexual relations between siblings or between parents and children. Babies who result from those unions are thought to be at significantly higher risk of genetic problems, the report said, but there is not enough data to be sure.
Motulsky said that the panel of experts began working on the cousin question about two years ago after a survey of counselors found a lot of misinformation in the advice given to people who wanted to know whether cousins could safely have children.
The article includes a personal account from a woman who said she had lived with her cousin for six years "and we are madly in love." When she became pregnant, her gynecologist warned that the child would be sickly and urged her to have an abortion. Describing herself as heartbroken, the woman had the abortion, which she called "the worst mistake of my life."
The small increase in risk is thought to occur because related people may be carrying some of the same disease-causing genes, inherited from common ancestors. Unrelated people share fewer genes, so their risk of illness is a bit lower.
2002 San Francisco Chronicle Page A - 3
Fears of passing defects to offspring overblown, research finds
Denise Grady, New York Times
Thursday, April 4, 2002
©2002 San Francisco Chronicle
URL:
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2002/04/04/MN91383.DTL
Contrary to widely held beliefs and long-standing taboos in America, first cousins can have children together without a great risk of birth defects or genetic disease, scientists are reporting today. They say there is no biological reason to discourage cousins from marrying.
First cousins are somewhat more likely than unrelated parents to have a child with a serious birth defect, mental retardation or genetic disease, but their increased risk is nowhere near as large as most people think, the scientists said.
In the general population, the risk that a child will be born with a problem such as spina bifida or cystic fibrosis is 3 to 4 percent; to that background risk, first cousins must add 1.7 to 2.8 percentage points, the researchers said.
Although the increase represents a near doubling of the risk, the result is still not considered large enough to discourage people from having children, said Dr. Arno Motulsky, a professor emeritus of medicine at the University of Washington and the senior author of the report.
"In terms of general risks in life, it's not very high," Motulsky said.
The report is being published today in the Journal of Genetic Counseling.
The researchers, a panel convened by the National Society of Genetic Counselors, based their conclusions on a review of six major studies conducted from 1965 to August 2000, involving many thousands of births.
Motulsky said medical geneticists had known for a long time that there was little or no harm in cousins marrying and having children. "Somehow, this hasn't become general knowledge," he said, even among doctors.
California is among the states that allow cousins to marry. But 24 states have laws forbidding marriage for first cousins and seven have limits like requiring genetic counseling. No countries in Europe have such prohibitions, and in parts of the Middle East, Africa and Asia, marriages between cousins are considered preferable.
Motulsky said many immigrants from cultures where cousin marriages are common are expected to continue the tradition in America, and doctors and genetic counselors should respect their wishes. He said the American laws against cousin marriage should be abolished.
Motulsky said researchers did not know why marriage between cousins was viewed with such distaste in America, although he said some of the revulsion may have stemmed from the eugenics movement that flourished here early in the 20th century.
It is not known how many cousins marry or live together. Estimates of marriages between related people, which include first cousins and more distant ones, range from less than 0.1 percent of the general population to 1.5 percent. In the past, small studies have found much higher rates in some areas:
A survey in 1942 found 18.7 percent in a small town in Kentucky, and a 1980 study found 33 percent in a Mennonite community in Kansas.
The report made a point of saying that the term "incest" should not be applied to cousins but only to sexual relations between siblings or between parents and children. Babies who result from those unions are thought to be at significantly higher risk of genetic problems, the report said, but there is not enough data to be sure.
Motulsky said that the panel of experts began working on the cousin question about two years ago after a survey of counselors found a lot of misinformation in the advice given to people who wanted to know whether cousins could safely have children.
The article includes a personal account from a woman who said she had lived with her cousin for six years "and we are madly in love." When she became pregnant, her gynecologist warned that the child would be sickly and urged her to have an abortion. Describing herself as heartbroken, the woman had the abortion, which she called "the worst mistake of my life."
The small increase in risk is thought to occur because related people may be carrying some of the same disease-causing genes, inherited from common ancestors. Unrelated people share fewer genes, so their risk of illness is a bit lower.
2002 San Francisco Chronicle Page A - 3
Didn't see it. 
