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Why Saudi Arabia Is Pushing Premarital Genetic Screening

59 points by ourmandave 9y ago

abusoufiyan 9y ago
This actually brings up some interesting questions. For a long time, many deemed marriages between cousins as undesirable precisely because of the unknown risk of genetic problems in the resultant offspring. But now, if scientific evidence can tell you that your marriage to your first or second cousin is highly unlikely to cause genetic defects in offspring, might that shift our understanding of such relations? I can't help but think this might usher in more and more acceptance towards such situations just as contraception and STD screening and medicine did for sexual activity between younger people and more partners.
- throwawaymanbot 9y ago
  ....are you asking for a friend?
- nkrisc 9y ago
  Over a long time? Maybe. But it won't happen overnight. In most cultures that taboo is cemented. Ask any random person who think it's taboo why it's taboo and I would wager they don't really know why, just that it is. As such, I don't think this is going to change minds, at least not for a while.
  - ars 9y ago
    > they don't really know why, just that it is This taboo does not come from the Bible, since the Bible does not prohibit cousin marriage. I assume the taboo comes from seeing problems in offspring. Scientifically, occasional cousin marriage is not usually a problem. It's only when it's repeated more than once that it starts to be a problem.
    - nkrisc 9y ago
      I made no mention of the Bible nor where the taboo comes from, but merely mentioned that is is a taboo that is cemented in some cultures and I posited that most people from those cultures aren't aware of why they think it's taboo beyond the fact their culture makes it taboo.
      - ars 9y ago
        I know you didn't. But a lot of people falsely think it comes from the Bible, so I figured I'd mention it.
- ars 9y ago
  > if scientific evidence can tell you that your marriage to your first or second cousin is highly unlikely to cause genetic defects in offspring The science is not there. It probably will never be there. We can only screen for certain conditions. Close marriage will turn up all sorts of new conditions no one knows about (ahead of time). Until the day we can make our DNA "perfect" close marriage will always be a problem. And on that day I suppose even sibling marriage (or incest) would not be a genetic problem.
  - shayaknyc 9y ago
    You're correct in that you can only test for things you know about (duh, you don't know what you don't know) so as far as screening goes, it's just a matter of how much you're screening FOR. It's also really easy to rule out which diseases are not likely to occur just by checking one person's DNA. You only have to screen where both samples can potentially combine to form something bad.
    - Ovah 9y ago
      Far from all hereditary disease are easy to rule based on genetic tests. You need to differentiate between Mendelian and Complex genetic disorders. While genetic tests are useful to indentiy disease caused by a single allele (Mendelian disorders), they today are inconclusive for many other Complex diseases, like rheumatoid arthritis, with a known genetic component. These disease are multifactorial: the interplay between several genes (variants) and environmental stimuli cause the disease. One of several genetic mutation must be present for the disease to occur, but without an environmental stimulus, the disease will never materialize. As such, even though we have acces to a full genom sequence, genetic tests are inherently limited and thus inconclusive in determining risk for many diseases.
- mc32 9y ago
  At that point you begin down the slippery slope. Most people would be repulsed by the very idea, but down the road who knows. "Culture" does indeed change. That said, I don't see being able to overcome the gut reaction.
- maxerickson 9y ago
  The cultural resistance to cousin marriage is already an overreaction to just the statistical odds of genetic diseases, without any screening. (Part of the explanation is that humans are not particularly genetically diverse overall)
ars 9y ago
Jews were able to essentially wipe out Tay–Sachs as an active disease by implementing https://en.wikipedia.org/wiki/Dor_Yeshorim https://en.wikipedia.org/wiki/Dor_Yeshorim People are still carriers, but there is little to no active disease for the screened conditions. So this kind of screening can work. (Wikipedia worked hard to appear "neutral" and found some criticism to include, but in actuality there is widespread support for this, and I hope they expand the list of conditions.)
- xkcd-sucks 9y ago
  Is this technically a eugenics program?
  - lucian1900 9y ago
    Yes, insofar as it matches the definition. Does it harm anyone to offer advice of this sort? I think not.
  - jerf 9y ago
    Since this is implemented by informing people carrying the recessive genes about each other before marriage or reproduction, it would be a definition of "eugenics" so broad as to fail to match the common denotation of the term that carries the huge connotational baggage. (Note I'm not dealing with dictionary terms here, but how I think people think of it; with such a loaded term here the denotation and connotation becomes harder than usual to separate.) It would not necessarily be an impossible stretching of the term, but as the vast, vast majority of people would not consider this a problematic solution it doesn't seem like it would really provide any advantage, and would run the risk of watering down the opprobrium attached to the term "eugenics" by including a thoroughly unobjectionable practice.
    - TeMPOraL 9y ago
      > and would run the risk of watering down the opprobrium attached to the term "eugenics" by including a thoroughly unobjectionable practice At the risk of touching things one is not supposed to say in this culture - wouldn't it be good to tone down that opprobrium, or at least cleanly separate out the things that are actually evil from things that are not? The connotational baggage carried by the term "eugenics" tend to infect serious discussions around genetic diseases and genetics in general, and people end up equating e.g. permanently curing genetic diseases (by removing them from the gene pool) with mass mutilation or murder of undesirable individuals (which is the evil part of the as-commonly-understood eugenics).
shayaknyc 9y ago
I think the genetic risks of first cousin consanguinity are far lower than one would initially think. The real problem occurs when there's multiple generations of 1st cousin consanguity - the likelihood of concentrating recessives, etc increases in subsequent generations. In fact, I believe historically speaking, there's a very large precedent going back centuries for first cousin marriages (resulting in offspring) and as far as I know, it's not illegal anywhere in the USA. Here's an article dated back in 2002 that discusses the genetic risks: http://www.nytimes.com/2002/04/04/us/few-risks-seen-to-the-children-of-1st-cousins.html http://www.nytimes.com/2002/04/04/us/few-risks-seen-to-the-c...

59 points by ourmandave 9y ago

This actually brings up some interesting questions. For a long time, many deemed marriages between cousins as undesirable precisely because of the unknown risk of genetic problems in the resultant offspring. But now, if scientific evidence can tell you that your marriage to your first or second cousin is highly unlikely to cause genetic defects in offspring, might that shift our understanding of such relations? I can't help but think this might usher in more and more acceptance towards such situations just as contraception and STD screening and medicine did for sexual activity between younger people and more partners.

throwawaymanbot 9y ago
....are you asking for a friend?
nkrisc 9y ago
Over a long time? Maybe. But it won't happen overnight. In most cultures that taboo is cemented. Ask any random person who think it's taboo why it's taboo and I would wager they don't really know why, just that it is. As such, I don't think this is going to change minds, at least not for a while.
- ars 9y ago
  > they don't really know why, just that it is This taboo does not come from the Bible, since the Bible does not prohibit cousin marriage. I assume the taboo comes from seeing problems in offspring. Scientifically, occasional cousin marriage is not usually a problem. It's only when it's repeated more than once that it starts to be a problem.
  - nkrisc 9y ago
    I made no mention of the Bible nor where the taboo comes from, but merely mentioned that is is a taboo that is cemented in some cultures and I posited that most people from those cultures aren't aware of why they think it's taboo beyond the fact their culture makes it taboo.
    - ars 9y ago
      I know you didn't. But a lot of people falsely think it comes from the Bible, so I figured I'd mention it.
ars 9y ago
> if scientific evidence can tell you that your marriage to your first or second cousin is highly unlikely to cause genetic defects in offspring The science is not there. It probably will never be there. We can only screen for certain conditions. Close marriage will turn up all sorts of new conditions no one knows about (ahead of time). Until the day we can make our DNA "perfect" close marriage will always be a problem. And on that day I suppose even sibling marriage (or incest) would not be a genetic problem.
- shayaknyc 9y ago
  You're correct in that you can only test for things you know about (duh, you don't know what you don't know) so as far as screening goes, it's just a matter of how much you're screening FOR. It's also really easy to rule out which diseases are not likely to occur just by checking one person's DNA. You only have to screen where both samples can potentially combine to form something bad.
  - Ovah 9y ago
    Far from all hereditary disease are easy to rule based on genetic tests. You need to differentiate between Mendelian and Complex genetic disorders. While genetic tests are useful to indentiy disease caused by a single allele (Mendelian disorders), they today are inconclusive for many other Complex diseases, like rheumatoid arthritis, with a known genetic component. These disease are multifactorial: the interplay between several genes (variants) and environmental stimuli cause the disease. One of several genetic mutation must be present for the disease to occur, but without an environmental stimulus, the disease will never materialize. As such, even though we have acces to a full genom sequence, genetic tests are inherently limited and thus inconclusive in determining risk for many diseases.
mc32 9y ago
At that point you begin down the slippery slope. Most people would be repulsed by the very idea, but down the road who knows. "Culture" does indeed change. That said, I don't see being able to overcome the gut reaction.
maxerickson 9y ago
The cultural resistance to cousin marriage is already an overreaction to just the statistical odds of genetic diseases, without any screening. (Part of the explanation is that humans are not particularly genetically diverse overall)

ars 9y ago

Jews were able to essentially wipe out Tay–Sachs as an active disease by implementing https://en.wikipedia.org/wiki/Dor_Yeshorim https://en.wikipedia.org/wiki/Dor_Yeshorim People are still carriers, but there is little to no active disease for the screened conditions. So this kind of screening can work. (Wikipedia worked hard to appear "neutral" and found some criticism to include, but in actuality there is widespread support for this, and I hope they expand the list of conditions.)

xkcd-sucks 9y ago
Is this technically a eugenics program?
- lucian1900 9y ago
  Yes, insofar as it matches the definition. Does it harm anyone to offer advice of this sort? I think not.
- jerf 9y ago
  Since this is implemented by informing people carrying the recessive genes about each other before marriage or reproduction, it would be a definition of "eugenics" so broad as to fail to match the common denotation of the term that carries the huge connotational baggage. (Note I'm not dealing with dictionary terms here, but how I think people think of it; with such a loaded term here the denotation and connotation becomes harder than usual to separate.) It would not necessarily be an impossible stretching of the term, but as the vast, vast majority of people would not consider this a problematic solution it doesn't seem like it would really provide any advantage, and would run the risk of watering down the opprobrium attached to the term "eugenics" by including a thoroughly unobjectionable practice.
  - TeMPOraL 9y ago
    > and would run the risk of watering down the opprobrium attached to the term "eugenics" by including a thoroughly unobjectionable practice At the risk of touching things one is not supposed to say in this culture - wouldn't it be good to tone down that opprobrium, or at least cleanly separate out the things that are actually evil from things that are not? The connotational baggage carried by the term "eugenics" tend to infect serious discussions around genetic diseases and genetics in general, and people end up equating e.g. permanently curing genetic diseases (by removing them from the gene pool) with mass mutilation or murder of undesirable individuals (which is the evil part of the as-commonly-understood eugenics).

shayaknyc 9y ago

I think the genetic risks of first cousin consanguinity are far lower than one would initially think. The real problem occurs when there's multiple generations of 1st cousin consanguity - the likelihood of concentrating recessives, etc increases in subsequent generations. In fact, I believe historically speaking, there's a very large precedent going back centuries for first cousin marriages (resulting in offspring) and as far as I know, it's not illegal anywhere in the USA. Here's an article dated back in 2002 that discusses the genetic risks: http://www.nytimes.com/2002/04/04/us/few-risks-seen-to-the-children-of-1st-cousins.html http://www.nytimes.com/2002/04/04/us/few-risks-seen-to-the-c...