Why have a total ban on inbreeding in humans when it is basically 50/50 between pro and con doing it?

Your question has an assumption that is not necessarily true. Who says it is 50/50 pro or con?

Generally, inbreeding causes too many genetic defects to be emphasized, so that it is just all around a bad idea. You mention the royal families of Europe, which had a high incidence, for a small population group, of hemophilia and mental retardation.

As @zenvelo says, “inbreeding causes too many genetic defects to be emphasized.” The recessive gene defects are more likely to manifest due to inbreeding. This has happen not only in human population; royal families. It also happens with animals.

It may not cause serious medical problems if done once or twice; however, left unchecked the problems will occur. The options really then become 1) checking genealogy before procreation to ensure there is not a lot of inbreeding, or 2) creating a ban. It is easier for society to create a ban then to have to check records for the amount of inbreeding. You mentioned Japan after the A-bombs and that is probably a pretty unique situation.

Besides that, we humans have a built-in taboo against it just to protect us from those genetic defects.

Your initial premis is flawed. I have no idea where the 50–50 number is anything but an offhand guesstimate.

And even tho you jokingly state that there are no Amish running around with three arms, there are significant numbers born with extra fingers and toes all linked to a very rare form of Dwarfism. And the only 50–50 number in that statistic is that 50% of those infants die shortly after birth due to genetically defective hearts from the same defective gene. (And of those who survive, most parents opt for surgical removal of the extra digits). So, just because they aren’t running around with extra fingers and toes, doesn’t diminish the heartache caused by the inbreeding which caused this defective gene to multiply in this particular population.

If you want a quick illustration of how recessive genes are able to wreak their havoc and exactly how precisely they were able to nail this down, there’s a fascinating article in Time magazine.

I can’t do links from iPhone but if you Google “inbreeding and dwarfism” and click on the link to Time magazine it’s really a fascinating read.

The British royal family produced a lot of genetic defects in the old days, you know. And a lot of stillborns and other things. England is a small country – about the size of Indiana, and it is very old. The people there tend not to marry foreigners very much, and the gene pool is about the size of a bucket. I have noticed that the health channel on TV has been doing documentaries on children in England who have been born with weird genetic disorders, which the scientists say could only happen if both parents carried the defect, and therefore would have to be related to each other. Case in point, the butterfly boy, whose skin rips like butterfly wings. And then two sisters who have a skin disorder that makes their skin keep sluffing off. Just two examples. You have to have a large gene pool to keep offspring healthy.

@Skaggfacemutt – it wasn’t a question of the British royal family not marrying foreigners (they are foreigners anyway!), it was a problem of marriage amongst European royal families that were close relatives. In order to avoid wars, royal families intermarried, eventually reducing their gene pool. So, the problem was not confined to England, it was all European royal families. I don’t think that generic disorders are particularly more prevalent in England than in any other country. I’d be interested to hear if anyone has any specific statistics that backs up either case.

@gmander Sorry, I do tend to shift gears when I write. I didn’t say that the royal family didn’t marry foreigners – I said the British people tend to marry locals. The royal families of Europe are all related to each other and for generations only married amongst each other, making their gene pool about the size of a raindrop.

@Hypocrisy_Central

“eeing there are no 3 armed Amish”

The Amish have such a high rate of genetic defects that they are routinely used as subjects in medical studies of such defects.

Kissing cousins is one thing, fucking and reproducing cousins is entirely different. It’s not genetically safe to make babies with your cousins because it typically produces children that are “retarded” in some form or fashion, or have birth defects.

@zenvelo*Your question has an assumption that is not necessarily true. Who says it is 50/50 pro or con?* It is an estimate seeing that those who would allude to the fact it is more than 50% risky considering many places on the globe in which it was done like the ancient Egyptians, which full sibling marriages accounted for 15 to 21 percent of all unions. Evidence found strongly suggests that sibling marriages were not only common but the preferred norm. Brother/sister unions were observed by Edward E. Evans-Pritchard ”[W]hen a boy reaches puberty he may take his sister and with her build their little hut near his mother’s home and go into it with his sister and lay her down and get on top of her—and they copulate” (1974, p. 107). Middleton (1962, p. 603) Father/daughter unions were common in Tonga. Many combinations of inbred unions have gone on and not nearly half were studied. To look at the disasters that had happened with the Amish and the British Royals and say that is indicative of all inbreeding would be to say because of 3 Mile Island and Chernobyl man should refrain from all use of nuclear power.

@optimisticpessimist “inbreeding causes too many genetic defects to be emphasized.” Really? Overall or in selective cases? As pointed out above there are many couplings that have not been studied and in some cases it was actually beneficial, in Arab populations reduction of overall cancer risk was associated with increased coefficient of inbreeding (Ulysses Ronquillo? You can look at the problems Charles II of Spain had but he was the product of about 6 centuries of inbreeding, hardly a case you’d see today. Hardly any of what the Amish and the Royals gone through you’d seen today because where it might happen in one maybe 2 generations, it has very little chances to go beyond that. Relaying back on science solely modern genetic and metabolic test can catch around 100 of these negative or arrant genes. Inbreeding has been used by breeders and ranchers for centuries to develop desired traits, more muscle to fat ratio in bulls and swine, more milk production, larger calves, etc. if it were that horrendous they would not risk having a herd of “retarded cows” for the sake of maybe having 30% more cows that could produce 15gal a day more milk than the rest?

@marinelife Besides that, we humans have a built-in taboo against it just to protect us from those genetic defects. Those who are regular sized decide to couple with Little People and have children are overlooking this “built-in” taboo against genetic defects? The possible outcome is there to see clearly in the height their mate don’t have. Second, this “built-in” protection device stops at coupling with family but not at diminishing one’s capacity with chemicals; not keeping ones mine sharp and un-inebriated?

@WillWorkForChocolate It’s not genetically safe to make babies with your cousins because it typically produces children that are “retarded” in some form or fashion, or have birth defects. In some cases it has been so but also sticking to just the science it has been happening all over the world, in Africa, Asia, Tonga, etc and those populations are not vastly more “retarded” than those places that haven’t done it routinely. The same way as certain genetic malformations can be doubled others can be erased. It is not safe for women past menopause to be giving birth but fertility clinics have not barred them, and there is no law preventing them.

At best it can be seen as a two-edged sword, with modern technology it can be used to correct certain family diseases or if used incorrect expand them. Basically it is the “ick” factor which isn’t scientific but since for the sake of this question it can’t exist inbreeding is like the movie Titanic; it is what it is, you either see a disaster film or a “chic flick” depending on what story line you want to follow.

This sentence does not demonstrate that the arguments are evenly weighed: It is an estimate seeing that those who would allude to the fact it is more than 50% risky considering many places on the globe in which it was done like the ancient Egyptians, which full sibling marriages accounted for 15 to 21 percent of all unions.

This link discusses sibling relationships as rare in Egypt, and mostly confined within royal families.

I think incestual relationships are much more rare than you assume.

@Hypocrisy_Central When most people stated a big problem was the increased occurrences of genetic defects, you take it down to, “Basically it is the “ick” factor…” Yes, “with modern technology it can be used to correct certain family diseases or if used incorrect expand them” or even make people aware they both carry a recessive gene with could affect their offspring. The ban can be a protective measure against recessive genes showing up in offspring so could genetic testing. Concerning cattle, after reading several sites on inbreeding (in cattle and other animals) almost any source stated, ‘the risk out weighs the benefits.’ I do not have the money for genetic testing, but nor do I have a desire to procreate with any relative of mine so it really does not matter to me.

@WillWorkForChocolate – re cousins ‘typically produces children that are “retarded”’. Complete nonsense. While a large number of US states have made marriage between first cousins illegal, there are many states where it is allowed and it is legal in all EU countries, so there is plenty of evidence to look at. Studies have shown that the additional rate of genetic conditions in first cousin marriages is a rise from 2% to 4%, that is hardly a case of ‘typical’ and few genetic disorders result in mental retardation in the first case.

How would such a ban effectively work?

You can’t ban inbreeding, it’s a profound invasion of personal freedom to legislate who a person can have as a sexual partner (among consenting adults of course).

@gmander While a large number of US states have made marriage between first cousins illegal, there are many states where it is allowed and it is legal in all EU countries, so there is plenty of evidence to look at. about have the nation here in the US, near 25 in all, I guess no one thought to mention the Rothschilds, Albert Einstein, Jerry Lee Lewis, among others. They didn’t have “You get babies with nine heads.“_” as was said in play _Brighton Beach Memoirs. Journal of Genetic Counseling determined that children parented by 1st cousins faced only about a 2–3% higher risk of birth defects about the same as a woman having a child at age 40 instead of age 30. Do we say after 40 you can’t have kids even though you have some ticks left on the biological clock? Scientifically speaking inbreeding poses lest risk than alcohol use pound for pound. Thanks for looking at the pure logic and keeping the “ick factor” in the vault, larvae that..

@Hypocrisy_Central Your argument is still fallacious. While defects are a relatively small risk of first cousins, that is only one generation. But inbreeding amongst siblings would magnify it, as would continued inbreeding amongst successive generations.

@zenvelo Yes it could worsen over subsequent generations but that is highly unlikely in any nation with tons of people and many entering legally and illegally every year. It would have to be a very close family to not look outside the fold even when opportunity is there. Regardless the fact that inbreeding done once or a second time in back to back generations do not pose such a detriment that todays people if they chose to should be barred from doing it. If the risk was 7 to 8 out of 10 then I could see but no greater risk than an old lady trying to puch a baby out….don’t quiite make the cut. Certainly not enough to scientifically bar it no questions asked.