If 1st cousins keep mating generation after generation ...

[Anonymous]

Anonymous wrote:

Anonymous wrote:Saudi Arabia, high incidence of inherited conditions.

I thought that was from marrying DOUBLE first cousins, which is like marrying siblings.

What is a DOUBLE 1st cousin?

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Saudi Arabia, high incidence of inherited conditions.

I thought that was from marrying DOUBLE first cousins, which is like marrying siblings.

What is a DOUBLE 1st cousin?

First cousin is when one of your parents is the sibling of one of their parents. Double first cousin is when both of your parents are the siblings of both of their parents. For example, two brothers married two sisters.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Any medical professionals out there? What is the effect on offspring, if first cousins keep producing children, generation after generation. Does this do something to their brain?

Inbreeding doubles the risk of birth defects and can trigger latent, recessive genes with regards to rare medical conditions.

For example, the fundamentalist Mormons have terribly high rates of a specific mental retardation that is very, very rare among the general population.

The polygamists? I saw a show about this. And they have as many kids as they can and the children are just completely incapacitated for their whole lives.

Why are the kids incapacitated their whole lives? Because they don't get any attention from their parents?

No, because fumarase deficiency is no joke. https://en.wikipedia.org/wiki/Fumarase_deficiency

[Anonymous]

Anonymous wrote:Their skin can turn blue.

Which demonstrates that a recessive gene can propagate in a community like this. But then again, those people lived into their eighties and nineties in rural Kentucky.

My guess is that a few hundred years ago, everyone in a given village in Europe was related in some way.

[Anonymous]

We are all cousins. Look up most recent common ancestor. For example, assuming three generations per century we would all have many millions of direct ancestors 1000 years ago. My ancestors are from various parts of Great Britain. The population of Great Britain during that time period was 2 million people. Statistically speaking, therefore, I am descended from every member of this population that has living descendants, which is about 80 percent of them.

[Anonymous]

Anonymous wrote:http://scienceblogs.com/gnxp/2009/04/14/inbreeding-the-downfall-of-the/

Charles II of Spain is really the classic case study for the dangers of inbreeding. Check out this pedigree:



His mother was his father's niece, his grandmother was also his aunt, another grandmother was also his great-grandmother, and all 8 great-grandparents were descended from the same couple. It's sort of surprising his parents managed to have any live offspring at all.

[Anonymous]

OP, I heard that it is really not that dangerous.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Infertility is another side effect. It is epidemic in the middle east, with as many as 25% of all couples unable to reproduce because of consanguinity. Iran pays for in vitro, surrogacy, donor eggs etc at state-run facilities because it has no choice if the population is to survive.

Persians don't actually marry cousins very often, and they have fewer children, making cousin marriage even less possible.

Unlike Saudi, where first cousins can easily number 50+, and the choices are much greater.

Google is your friend, my dear. Persians most definitely do practice consanguineous marriages, with devastating effects on their fertility.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Their skin can turn blue.

Which demonstrates that a recessive gene can propagate in a community like this. But then again, those people lived into their eighties and nineties in rural Kentucky.

My guess is that a few hundred years ago, everyone in a given village in Europe was related in some way.

What just in Europe? Villages in Africa, Asia, etc were not having this problem?

[Anonymous]

Why, my Euro grandma married a guy from 20km away village! She went to another village and got brown haired, brown eyes husband unlike her own blue eyes, blond cousins! It was a good thing too, since she couldn't "accidentally" mistake him for a cousin, if you know what I mean?

[Anonymous]

Anonymous wrote:OP, I heard that it is really not that dangerous.

It's not dangerous once, as an isolated case. It becomes dangerous the closer and tighter a family tree gets.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Infertility is another side effect. It is epidemic in the middle east, with as many as 25% of all couples unable to reproduce because of consanguinity. Iran pays for in vitro, surrogacy, donor eggs etc at state-run facilities because it has no choice if the population is to survive.

Persians don't actually marry cousins very often, and they have fewer children, making cousin marriage even less possible.

Unlike Saudi, where first cousins can easily number 50+, and the choices are much greater.

Google is your friend, my dear. Persians most definitely do practice consanguineous marriages, with devastating effects on their fertility.

Iranians do practice consanguineous marriage, but nowhere near the rate of the Gulf area. But Iran has an infertility rate of nearly 25%, the highest in the world. Perhaps not so coincidentally, Iran also has one of the highest rates of STDs in the world, particularly chlamydia, which is known to affect fertility. Estimates of chlamydia rates in Iranian women range from 12% to 21% vs 0.6% in U.S. women.

Here is an article that puts it together:

http://www.meforum.org/5000/strategic-implications-iran-std

Some may argue that this is a biased publication, and I would generally agree. However, it is based on references that come from academic studies by Iranians like the following and the thesis of high STDs thus high infertility in Iran seems relatively well supported:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3398636/