Inbreeding

[DragonRider5624]

First cousins? I don't much of the harm. Siblings is different. The genetics is pretty darn close and with constant reproduction of the two could be harmful with the same dna and all..

This. Inbreeding is definetly not for me, but that's just me. The fact is that cousins have only half of the genes that you do, because if they were related to you by their father, their mother would pass down genetically different genes.

[olympe]

Uh, check your maths. About shared genes:

 

Between parent/child: 50% genes in common (of the genes that vary between humans, that is)

Between full siblings: roughly 50% genes in common (may be somewhere between 0 and 100%, but around 50% is most likely)

Between half siblings: roughly 25% genes in common (may vary between 0% and 50%, but around 25% is most likely)

Between niece/uncle or nephew/aunt: roughly 25% genes in common

Between first cousins: roughly 12.5% genes in common

Between second cousins: roughly 3.125% genes in common

 

So, yes, inbreeding between cousins is a very bad thing. /sarcasm

Sure, there is an increased risk of the offspring carrying two recessive genes that cause them problems (like, uh, albinism) up to being lethal.

 

Hemophilia, like it occured in European royal families, however, does not occcur due to inbreeding. It's a recessive, sex-linked disorder, meaning that women who carry the gene for hemophilia don't show that they do, but half their sons will suffer from the disorder, and half their daughters will be carriers. Hemophilia in women, however, is usually attributed to inbreeding, as they need to get one hemophilia gene from each parent. Considering that the respective gene is rather rare, it's unlikely for two unrelated individuals to possess it. However, the fact that the disorder spread through many royal families of Europe is attested to the fact that they all have Queen Victoria, who was a carrier for hemophilia, as their ancestress.

 

On another note, roughly 1/3 of all cases of hemophilia are not inherited, but caused by spontaneous mutations. (Which, contrary to common belief, don't have anything to do with inbreeding.) Queen Victoria, from whom the hemophilia in European royalty came, was (obviously) such a case of a spontaneous mutation.

[-platinum-draco-]

Uh, check your maths. About shared genes:

 

Between parent/child: 50% genes in common (of the genes that vary between humans, that is)

Between full siblings: roughly 50% genes in common (may be somewhere between 0 and 100%, but around 50% is most likely)

Between half siblings: roughly 25% genes in common (may vary between 0% and 50%, but around 25% is most likely)

Between niece/uncle or nephew/aunt: roughly 25% genes in common

Between first cousins: roughly 12.5% genes in common

Between second cousins: roughly 3.125% genes in common

 

So, yes, inbreeding between cousins is a very bad thing. /sarcasm

Sure, there is an increased risk of the offspring carrying two recessive genes that cause them problems (like, uh, albinism) up to being lethal.

 

Hemophilia, like it occured in European royal families, however, does not occcur due to inbreeding. It's a recessive, sex-linked disorder, meaning that women who carry the gene for hemophilia don't show that they do, but half their sons will suffer from the disorder, and half their daughters will be carriers. Hemophilia in women, however, is usually attributed to inbreeding, as they need to get one hemophilia gene from each parent. Considering that the respective gene is rather rare, it's unlikely for two unrelated individuals to possess it. However, the fact that the disorder spread through many royal families of Europe is attested to the fact that they all have Queen Victoria, who was a carrier for hemophilia, as their ancestress.

 

On another note, roughly 1/3 of all cases of hemophilia are not inherited, but caused by spontaneous mutations. (Which, contrary to common belief, don't have anything to do with inbreeding.) Queen Victoria, from whom the hemophilia in European royalty came, was (obviously) such a case of a spontaneous mutation.

Out of curiosity, how many genes are shared between two different unrelated people?

[olympe]

Most of them. I mean, we share about 98% or more with chimpanzees, so it should be even more between two humans, right? Probably more than 99% would be my guess.

[Chiaki]

For the religious ones, aren't we all related?

Actually all modern humans stem from a single group of people who emigrated from Africa about 2,000 generations ago and spread throughout Eurasia over thousands of years.

 

Personally I wouldn't inbreed both for the cultural and genetic reasons

[Brite]

Don't some cultures still do so?

[*~Soren~*]

Me personally I would never inbreed for the genetic issues, but I totally understand that its other peoples' decisions. So while I don't really agree with it if it can affect the offspring, I'm not going to go around telling people what they can and can't do.

[elderberrysyrup]

The genetic issues for one generation really isn't a problem. It's not twins making babies with twins making babies with twins, here.

[Princess Artemis]

The genetic issues for one generation really isn't a problem. It's not twins making babies with twins making babies with twins, here.

That's the thing, it's not inbreeding if it's only one generation. It needs to be done repeatedly in order to be inbreeding.

[Coryn02]

Inbreeding? Absolutely disgusting thought. The same genes between close relatives WILL cause some problems with their children.

 

But when it comes to DC dragons...? Don't care.

[elderberrysyrup]

That's the thing, it's not inbreeding if it's only one generation. It needs to be done repeatedly in order to be inbreeding.

Oh, well then, I just figured it was relatives mucking it up in general. If it's over many many generations then we'll have problems.

 

I am a little peeved that many of the opinions against inbreeding is largely an 'ick factor' rather than anything that can actually be discussed.

[Brite]

Oh, well then, I just figured it was relatives mucking it up in general. If it's over many many generations then we'll have problems.

 

I am a little peeved that many of the opinions against inbreeding is largely an 'ick factor' rather than anything that can actually be discussed.

So constant breeding with one couple or does it have to be gen by gen?

[tanglepelt3]

I don't know anything[ /I] about inbreeding, but it doesn't sound very good.

[hazeh]

For those of you who "squick" at the thought of sibling pairings or those of other intermediate family, what if those members had never known each other personally? Take the brother and sister example, separated by birth and by some freaky chance meeting each other without any idea they were fully related. If they fell in love and got married, what would be so different? No one would know.

[Brite]

For those of you who "squick" at the thought of sibling pairings or those of other intermediate family, what if those members had never known each other personally? Take the brother and sister example, separated by birth and by some freaky chance meeting each other without any idea they were fully related. If they fell in love and got married, what would be so different? No one would know.

Knowing the way over religious people are, they would probably be harassed if others found out.

[The Evil Doer]

For those of you who "squick" at the thought of sibling pairings or those of other intermediate family, what if those members had never known each other personally? Take the brother and sister example, separated by birth and by some freaky chance meeting each other without any idea they were fully related. If they fell in love and got married, what would be so different? No one would know.

If nobody knows about something, it makes it cool ?

[hazeh]

If nobody knows about something, it makes it cool ?

That's my point.

 

Edit: That point being, NO one would know. Say it was discovered said couple had genetic testing after a long time of being happily married and found that they were full siblings. To me, this does not squick me out at all. What makes siblings siblings, in my eyes, is the personal connection AS siblings. Not the blood. Sure, the genetic defects would have to be taken into account, but in my personal view, if they did not grow up AS brother and sister, then there should be no problem.

Edited December 6, 2011 by Shiny Hazard Sign

[The Evil Doer]

And my point was... Once they get married, have a kid and realize the kid has the same set of genes, wont that mess them up completely ?

While for you ignorance is bliss works fine I doubt it works fine for everyone else, I would certainly not be cool with it, in a same manner I would rather know if my girl is cheating on me than to be a happy yet an ignorant fool...

Just my opinion though....

 

 

Edit - Genetic defects are rarely an issue, for it to be an issue there has to be a genetic defect within the family, "defectless" siblings will produce a "defectless" baby (genetically speaking), to you sister and brother is ok, to me it just isnt right, but the good thing about the whole concept is that whoever other people choose to be with is none of our business so, you are correct to think the way you do, and Im correct to think the way I do, no right or wrong here....

Edited December 6, 2011 by The Evil Doer

[DarkEternity]

Out of curiosity, how many genes are shared between two different unrelated people?

We share /all/ genes in common with other humans. Only the alleles (alternate forms of the same gene) differ within the species.

Edited December 6, 2011 by DarkEternity

[Brite]

We share /all/ genes in common with other humans. Only the alleles (alternate forms of the same gene) differ within the species.

So is it just a myth that inbreeding causes mental retardation in children?

[sparrowo3o]

^^

No. At least, not according to my AP biology textbook.

[hazeh]

And my point was... Once they get married, have a kid and realize the kid has the same set of genes, wont that mess them up completely ?

While for you ignorance is bliss works fine I doubt it works fine for everyone else, I would certainly not be cool with it, in a same manner I would rather know if my girl is cheating on me than to be a happy yet an ignorant fool...

Just my opinion though....

While I'm sure it would be rather disconcerting for the married couple, I do not believe that knowing they were related as such after being together as a romantic couple equals actually being raised together as brother and sister and then getting married. Such as I would not marry by adopted brother. He would be my brother, no matter if we shared genetics or not. Blood isn't the only thing that should be held accountable as a family tie. I just discovered over the summer that I have two half-brothers by blood, but I don't consider them family (yet).

 

If those people are not introduced in anyway as family, I do not find much of an issue with it.

[7Deadly$ins]

So is it just a myth that inbreeding causes mental retardation in children?

Inbreeding doesn't create problems all on it's own. Inbreeding increases the frequency of similar genes. It can cause problems when the genes are repeated enough, but it can also create good mutations, too. That's why animals are sometimes intentionally inbred; with hopes of repeating and "locking in" desired traits.

[Walker]

I'm one of the few people I've ever met who doesn't really have a problem with it. I mean, no, I don't have an immediate "ick" factor to it. And if I'm going to go jump in one thread and say "love is love," I've got to stick to my guns and say the same for an incestuous relationship too. Love is love. And if it happens to be love with a related individual, so be it; I have no issue with it. As for the genetic aspect of it, I'd just say be careful about having children. Make sure you're prepared for what might happen; have your child tested for genetic diseases through amniocentesis if you're willing to take the risks of that procedure; keep in regular contact with doctors before and after your child is born.

[-platinum-draco-]

We share /all/ genes in common with other humans. Only the alleles (alternate forms of the same gene) differ within the species.

What I meant. I was curios what the average amount of alleles (a word I did not know) were shared, on average, between humans.