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Dec 22, 2008 08:30 PM | 40
Inbreeding is the source of jokes about British royalty and is associated with increased birth defects among offspring. The practice is so reviled that 31 U.S. states ban marriage between first cousins or allow it only if the couple has undergone genetic counseling or at least one partner is sterile or no longer fertile because of age.
But those laws "seem ill-advised" and "should be repealed," a geneticist and medical historian write in today's PLoS Biology. "Neither the scientific nor social assumptions that informed them are any longer defensible."
The US "cousin marriage" prohibition stretches back to the 1858, when Kansas barred such marriages; Texas was the most recent state to pass a ban, in 2005, write Diane Paul, a political scientist emeritus at the University of Massachusetts, Boston, and Hamish Spencer, head of zoology at the University of Otago in New Zealand. (European countries didn’t ban the practice because there, "the rich and noble were marrying" their cousins, Spencer tells us. "In America it was immigrants and the rural poor — a much easier target of legislation than your monarch.")
First cousins share about an eighth, or 12.5 percent, of their genes, according to a 2002 study in the Journal of Genetic Counseling. Because of that overlap, there's a 1.7 percent to 2.8 higher risk of intellectual disability and genetic disorders, including seizures and metabolic errors among children whose parents are first cousins than among the general population, says Robin Bennett, a certified genetic counselor and lead author of that research.
That elevated risk is "comparable to a 40-year-old woman having children and we consider that perfectly acceptable," Spencer tells ScientificAmerican.com. "I can't imagine a law saying they're not allowed to have children."
The father of evolution, Charles Darwin, married his first cousin, Emma Wedgwood, as did Albert Einstein when he walked down the aisle with cousin Elsa. But while marriage between first cousins occurs often in some parts of the world, and was not uncommon among immigrants and the rural poor during early American history, the practice is rare in the West, Spencer says.
"It's not an issue because most people aren’t interested in their first cousin," Spencer admits. "But it does affect some individuals and it doesn’t seem particularly fair."
It's worth noting that sex between more distant cousins may actually offer reproductive advantages. Pairings between third and fourth cousins result in more offspring and grandkids than more conventional couplings between folks who aren’t related, the Icelandic biotech company deCODE genetics reported in February.
Image of DNA by iStockphoto/Luis M. Molina
Tags:
genetic mutations,
incest,
inbreeding
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40 Comments
Add CommentGood, so cousins can marry, but still not gay people. Gata love the justice system...
Reply | Report Abuse | Link to thisEinstein's 2nd wife was his cousin, and they didn't have kids together (bad example). And frankly, I don't think it's "perfectly acceptable" for older women to have children. The risk of birth defects is not something a child - who never asked to be born - should have to live with.
Reply | Report Abuse | Link to thisagenthucky; Ummm....according to the article, the laws against cousins marrying are outdated, but still exist. Your point is inapplicable.
Reply | Report Abuse | Link to thisOf course it is "perfectly acceptable" for older women to have children, as long as they take precautions to have a healthy newborn. What is "older" anyhow? After age 30?
Reply | Report Abuse | Link to this"The practice is so reviled that 31 U.S. states ban marriage between first cousins or allow it only if the couple has undergone genetic counseling or at least one partner is sterile or no longer fertile because of age."
Reply | Report Abuse | Link to thisMy point being that there are circumstances allowing these cousins to marry given they take the proper care, when gay marriage has been outlawed by a technicality. According to this article, there is a 1.7 to 2.8 chance a gay couple will raise a kid with less birth defects than if two cousins were married and have a kid.
"It's not an issue because most people arent interested in their first cousin," Spencer admits. "But it does affect some individuals and it doesnt seem particularly fair."
It doesn't seem particularly fair? There is scientific data to support these laws banning the marriage. Not that I defend them, but there is NO scientific data to support the ban on gay marriage. It is sematics.
Inapplicable it is not, I am showing how unfair the public and government can be given the two situations presented.
especially if we see an overturn in the law because of this data.
Reply | Report Abuse | Link to thisAlso, I believe they mention it would be comparable to a 40 year old having children
The author of this article has chosen for whatever reason to ignore the real crux of the matter. A single first cousin marriage may have relatively low risk to offspring. The problem is that when first cousin marriage becomes acceptable in cultures, it happens again and again across the generations leading to significant increases in children with genetic problems.
Reply | Report Abuse | Link to thisThe author mentions the Royal families of Europe. Let's take a larger example. The Bedouin have a cultural practice of cousins marrying. Almost 65% of couples are cousins. This isn't a single generation that decided, "hey, cousins should marry" but many generations of cousins marrying. The result.... a much much higher rate of children born with genetic problems.
That is why those laws are on the books. Not to stop a pair of cousins from marrying but to stop this from becoming a cultural practice leading to the degradation of the gene pool.
First, Lisa brings up a fair point. It is not the practice of 2 cousins reproducing that is the problem...it is the practice of cousins marrying over a few hundred years that will have compounded effects that is the real issue. Before states should make any changes I would like to see studies that consider the compounding effects of several generations cousin-offspring.
Reply | Report Abuse | Link to thisSecond, Agenthucky you're completely off base. This article has nothing to do with gay rights. Further, your contention that a gay couple can have a baby that is statistically less likely to have problems the a cousin-couple is simply false. Gay couples can't have children that share genetic material from BOTH couples, therefore your political jab is intellectually inconsequential. Further, the article was claiming there was an injustice, and that injustice was based on SCIENCE!! Whether a state recognizes gay marriage and whether you are for or against gay marriage is a political/moral/societal question...it is NOT a scientific question. Finally, its completely and totally off the topic.
That's right and not only should they not marry but should also have to register as a sex offender,for engaging in sick perverted immoral acts with other sinful individuals.
Reply | Report Abuse | Link to thisWhich, going on your posting, jaxbuster, it obviously gives you a frisson of self-righteousness to contemplate.
Reply | Report Abuse | Link to thisHey, maybe first cousins could catagorize themselves as a class of people and we could call them cuzosexuals or cuzzes and they could flaunt their sexuality all day everyday in the faces of people who would ordinarily be disinterested and they could learn to affect accents and "dress" the part and have big parades to give us all a window into their private sex lives (as though we were interested) and demand that we accept what we wouldn't even know about in the first place if they kept discreet what should already be none of our business in the first place. We could talk and talk and talk about their sexuality and preference all the time and even forget what other things make them interesting and human. Boy, that would sure be fun and think how they could continually be a new hot button topic and could raise issues over and over about how they aren't treated fairly because someone just plain got tired of hearing about their sexuality ALL the time and began to shun them.
Reply | Report Abuse | Link to thisHey, maybe first cousins could catagorize themselves as a class of people and we could call them cuzosexuals or cuzzes and they could flaunt their sexuality all day everyday in the faces of people who would ordinarily be disinterested and they could learn to affect accents and "dress" the part and have big parades to give us all a window into their private sex lives (as though we were interested) and demand that we accept what we wouldn't even know about in the first place if they kept discreet what should already be none of our business in the first place. We could talk and talk and talk about their sexuality and preference all the time and even forget what other things make them interesting and human. Boy, that would sure be fun and think how they could continually be a new hot button topic and could raise issues over and over about how they aren't treated fairly because someone just plain got tired of hearing about their sexuality ALL the time and began to shun them.
Reply | Report Abuse | Link to thisHey, maybe first cousins could catagorize themselves as a class of people and we could call them cuzosexuals or cuzzes and they could flaunt their sexuality all day everyday in the faces of people who would ordinarily be disinterested and they could learn to affect accents and "dress" the part and have big parades to give us all a window into their private sex lives (as though we were interested) and demand that we accept what we wouldn't even know about in the first place if they kept discreet what should already be none of our business in the first place. We could talk and talk and talk about their sexuality and preference all the time and even forget what other things make them interesting and human. Boy, that would sure be fun and think how they could continually be a new hot button topic and could raise issues over and over about how they aren't treated fairly because someone just plain got tired of hearing about their sexuality ALL the time and began to shun them.
Reply | Report Abuse | Link to thisThe article is speculation about something that has not occurred; i.e. the repeal of laws banning the marriage of first cousins. Just because a person says something shouldn't continue does not necessarily mean it reflects the majority of opinion on the matter.
Reply | Report Abuse | Link to thisThe first generation, as noted, does not suffer serious consequences however the article neglects to mention what happens after several generations of cousins reproducing with cousins.
Reply | Report Abuse | Link to this-PJW
This article is a personal opinion regarding the current ban on marriage between first cousins or closer relations. We need to remember that just because a person airs their subjective opinion on a matter, it does not mean that the opinion conforms with the majority of society's view, which caused the legislation to be proposed and passed in each of those 31 states in the first place.
Reply | Report Abuse | Link to thisMy father was my mother's uncle and I have for most of my life hidden that fact from people and family that weren't aware of the connection. I have an older sister, we're both past 70 and quite healthy. Our four children between us are quite normal and above average intellectually. I have three grandchildren who are bright, one particularly gifted. As a child I had definite attention deficit issues and to a great extent still do, and at times situational depression. My medical profile is typical of a male 70+ (hypertension). Our genetic background is Ashkenazi Jewish. I usually face the issue of my mother's maiden name being the same as her married name by admitting that they were distant cousins, but have always felt a certain embarrassment.
Reply | Report Abuse | Link to thisagenthucky, you are correct that this shows an improper bias against gay couples. I think the problem is visibility. If a gay couple were to marry, it's rather obvious that they're gay; but if heterosexual cousins marry, most people would never even know they were cousins.
Reply | Report Abuse | Link to thisUntil the general stigma associated with homosexuality is removed, homosexual marriage will not be generally accepted, especially with the high levels of conservatism and religious fundamentalism present in this country.
In all fairness, I think agenthucky's first response was just to show the overall unfairness of the situation: there ARE scientific reasons against first cousins marrying -- especially, as pointed out, over generations -- but there is NOT a single, scientific reason to bar gay marriage. Even the social/moral/political question is steeped in prejudice and hate, as evidenced by jaxbuster response.
Reply | Report Abuse | Link to thisagenthucky, take a note from Elton John and quit trying to call it marriage. Civil Unions have the exact same rights and are being recognized by more states. Homosexuality is not illegal, even though my personal beliefs are that it is wrong. I still view everyone as human and with them to be treated as such. Why argue semantics, when clearly your human rights are upheld? So what if the religious groups believe marriage should be between one man and one woman? Call it what you want, but stop saying that gay 'marriage' is banned, when in the US it is not banned but simply renamed to Civil Union.
Reply | Report Abuse | Link to thisAgenthucky: They're comparing this to an older women (in her 40s or so) having a baby. The reason why inbreeding was banned in the first place, was because of the obvious outcome of occasional birth defects. Now that science has comprehended that particular subject better, they know that the ratio in which this happens is actually equal to or less then the ratio of a women in her 40s having a baby, which is NOT outlawed.
Reply | Report Abuse | Link to thisThe issue of gay marriage, from the scientific community, stands at this:
Males have penis', women have vaginas. Penis' function is to be inserted into vaginas, in order to reproduce.
There you have it, so quit arguing politics and social discord on a scientific magazine's website. Go join a support group or something.
Agenthucky: They're comparing this to an older women (in her 40s or so) having a baby. The reason why inbreeding was banned in the first place, was because of the obvious outcome of occasional birth defects. Now that science has comprehended that particular subject better, they know that the ratio in which this happens is actually equal to or less then the ratio of a women in her 40s having a baby, which is NOT outlawed.
Reply | Report Abuse | Link to thisThe issue of gay marriage, from the scientific community, stands at this:
Males have penis', women have vaginas. Penis' function is to be inserted into vaginas, in order to reproduce.
There you have it, so quit arguing politics and social discord on a scientific magazine's website. Go join a support group or something.
Lisa86 - if there were a 'recommend this' button next to your comment, I'd hit it! Great point.
Reply | Report Abuse | Link to thisDo you honestly think that just because it would be legal, people would suddenly indulge in cousin marriages? That's ridiculous. It's stated in the article that people from the Western culture are not interested in their cousins anyway. Those in developing countries find suitors that live in close proximity to them, which happen to be their cousins.
Reply | Report Abuse | Link to thisAnother reason why people marry their cousins is because of monopolizing the family wealth and/or power, which is also not an issue for the majority of the population.
Basically, when it all comes down to it, the argument against cousin marriages is that it's 'not fair' for children to be born with genetic defects? Are you saying that such children have a 'lower' value of life? Who are we to judge?
Lisa96: I think he's addressing the rights of certain individuals who find that they are indeed in love, despite having that relation. I don't think the author is saying anything about a collective generational decision.
Reply | Report Abuse | Link to thisWhat about articles like this?
Reply | Report Abuse | Link to thishttp://www.boingboing.net/2006/08/31/inbred-fundamentalis.html
I'm not aware that you have the right to marry anyone just because you love them. Obviously, gays are not allowed to marry. Siblings are not allowed to marry.
Reply | Report Abuse | Link to thisThere is a real, serious social need to stop cousin marriages from becoming acceptable within society. In the cultures which allow it, there is a significant increase in birth defects. In Pakistan, 55% of married couples are first cousins and there is a 13 fold increase in genetic disorders. Despite the fact that Pakistanis in England represent only 3% of the population, they have almost a third of all children born with genetic disorders. (http://news.bbc.co.uk/2/hi/programmes/newsnight/4442010.stm) This isn't because of a single couple marrying but because it has been happening for generations.
It may be that in most American communities first cousin marriages would never become popular but keep in mind, that we have a substantial immigrant population here who DO come from cultures which encourage cousin marriages. Allowing those to progress would increase the number of children born with defects because the parents are very likely to be the offspring of generations of cousin marriages.
This is a foolish idea. It is morally unsound.
From purely scientific point of view, marriage encourages the birth of children. If the western world was to encourage marriage between first-cousins, it would come to point where the future generations will question our right to take such a position, knowing the 'risk' involved with 'inter-breeding.' whether the risk is 1% or 50%.
Reply | Report Abuse | Link to thisI personally feel that as a generation, we have to safeguard the world for the future generation, who in turn, will protect it for the next. So what was a scientific debate, whether to allow first-cousin marriages, becomes political one. Which must not be justified by the individual case, but by a whole nation.
For those concerned about gay marriages not being legal, it is purely a semantic issue. Politics plays no role in it and I am personally disgusted that people would say that it does. Gay people have as much right to be together as the next couple however, however marriage is about bringing together 2 people of opposite sex, and recognize their love before the lord "according to the religious beliefs laid out in the bible" Gay people are not recognized as acceptable in the Christian religion, and therefore are not granted the right of "marriage". Instead they have their own way of being recognized, bot by the American government and by the gay community.
Sam11, "marriage" is not something that is contemplated in a scientific setting. Marriage is governmental construct to further certain goals of the government, such as procreation, wealth sustainment, security, and responsibility to children and aging parents/grandparents.
Reply | Report Abuse | Link to thisTo bring religion into this argument is nothing but a pathetic attempt to hijack this blog. The article references INCEST not gay marriage. Your dogmatic religious preferences have no bearing on this discussion. Furthermore, there are many many more religions than just christianity that recognize marriage.
There are several churches that WILL perform gay marriage in their church. The contemporary question of gay marriage ONLY relates to government recognized marriage, which is entirely secular in nature and requires NO religious component. Because its entirely governmental, nearly by definition makes it a judicial and political question. To suggest otherwise is to completely miss the point of the discussion.
It's becoming widely recognized that the the incest taboo is a component of our instinctual behavior. Primates when they reach their reproductive stage will avoid mating with others with whom they've routinely shared their toilet midden when young.
Reply | Report Abuse | Link to thisYou're right about that. We should get rid of the word marriage in legal transactions. We don't call birth certificates baptism records anymore,do we?
Reply | Report Abuse | Link to thisShould the government ever restrict a person from marrying another? Marriage of first cousins may not be a social norm in the west, but restricting the choice of who to marry should be left to the individuals only. If marriage is restricted perhaps the government should also restrict who has children. A 17 year old meth user or a 45 year old vegetarian? Council begin your law-making. Ridiculous.The point is one should have the right to choose not the government.
Reply | Report Abuse | Link to thisHOW HARD IS IT, FIRST COUSINS HAVING KIDS, MEAN OPPOSITE SEX....
Reply | Report Abuse | Link to thisCAMPARING APPLES TO ORANGES, SOME PEOPLE WILL GO TO ANY LENGTHS TO JUSTIFY THEIR OPINION.
HOW HARD IS IT, FIRST COUSINS HAVING KIDS = OPPOSITE SEX, LIKE CAMPARING APPLES TO ORANGES. SOME WILL GO TO ANY LENGTH TO JUSTIFY THEIR OPINION. NO MATTER WHAT THE STRETCH.
Reply | Report Abuse | Link to thisHOW HARD IS IT, FIRST COUSINS HAVING KIDS = OPPOSITE SEX, LIKE CAMPARING APPLES TO ORANGES. SOME WILL GO TO ANY LENGTH TO JUSTIFY THEIR OPINION. NO MATTER WHAT THE STRETCH.
Reply | Report Abuse | Link to thiscameragrrl said "I don't think it's 'perfectly acceptable' for older women to have children." Given the affects of over population, I don't think it acceptable for any women to spawn. Ovaries and gonads should be removed at birth, and we ought to let the non-human world take over.
Reply | Report Abuse | Link to thisRG the LG
I agree with you. One of the main reasons why our society accepts births in women over 40 is that we have no practical way of enforcing a ban on them.
Reply | Report Abuse | Link to thisThe increased riskof mental defects in and of themselves is probably understated since I am sure they measured only gross abnormalities not subtle but debilitating defects that don't show up until much later. Further mental defects are not the only ones to worry about. Blood disorders, gistive disorders, skin disorders, infact every system of the body can be compromised by recessive traits. The simple fact is that no one within reach of the law has to marry their cousin for lack of alternatives. If some family hidden in apalachia or the pine barrens marries their cousin because everyone in thioer town is relatred, sobeit but we do not have to sanction it in our general society. It is just not fair to the kids or the society that will have to take care of them.
The Darwin example was a bad one too. He often lamented marrying his cousin despite loving her because of the ill effects it had on his childrens helath and well-being. Further he attributed the death of one of them to the incest.
Reply | Report Abuse | Link to thisHaving taken a couple of out of the norm classes and sat in on some marriage, incest, gay specific lectures about such ideas mentioned not only in the article, but brought up by the viewers I find this article rather interesting and can't wait to broach the topic in my repro/anat class on Monday.
Reply | Report Abuse | Link to thisThere are many factors here that have yet to be explored (such as the long term effects of closely related incestuous births). I hope that we will be able to glean more data from those areas which do not ban such acts as to determine the full extent of these issues. Data, I might add, that is as pure in the scientific community as we can get.
I would also like to add that although I am not into incest because of cultural upbringing I do not wish to inhibit others from doing as they please as long as it does not hurt me. I know there is some extent of not letting one hurt themselves but I can always see loopholes in this system for both sides which can make or break arguments either way.
I also feel and have been exposed to the idea that we should remake our idea of marriage and such. I do think it is rather bothersome that I cannot get married in certain states due to the dislike of the idea of "gay" marriage, but I find it more concerning that they can ban incest without the proper data to conclude their findings. They may be fudging the line of acceptable to the point of which I am not comfortable. There may be truth or there may not be truth in the idea that closely related siblings over time will cause genetic defects, but there's much more to study than the math behind it. How likely is it that 10+ generations will marry and breed together? If the chain is broken does the risk stay? If the chain is broken and repaired do the risks still exists at increasing amounts or does it wipe the slate clean?
So much more needs to be studied about this topic before any law should be passed one way or the other.
Incest, like most words, has many meanings. Most of the posts on this site refer to the dictionary meaning of the word. This application is extremely narrow. Think of childhood sexual abuse by a relative or other person in authority over a child--someone who has access to the child and the power to affect her day to day survival.
Reply | Report Abuse | Link to thisAs a counselor, I could relate numerous stories about children who were robbed of their voice, their power, and yes--even their sense of self--by the trauma of incest perpetrated against them. If these victims become locked into the shame, degradation, and fear --terror actually-- that is characteristic of childhood incest, they may assume learned helplessness and remain in the situation long after becoming an adult. They have aged chronilogically but remained in a previous stage emotionally. Trauma does strange things to people, especially when it begins at an early age and the child is barraged by it throughout the developmental stages of his or her life.
What would happen to this child-adult if incest was legalized? The same overbearing threats, mistreatment, and manipulation that imprisoned her (or him) as a child would be condoned by the laws of our land.
This must not happen! It may begin as marriage between cousins--but the legalization of incest in any form would most certainly lead to normalizing a practice that provides for the ultimate and final destruction of children victimized by fathers and step-fathers (statistically the most prevalent perpetrators of incest).
Many young victims (some of whom escape by going to college or some other rite of passage) would be entraped for the rest of their lives.