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Friends are as genetically similar as fourth cousins

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Re: Friends are as genetically similar as fourth cousins

#61

I live in Toronto, and frankly I doubt my Panjabi, Sri Lankan, Chinese, and Korean friends are as genetically similar as my fourth cousins.

It could be that you share certain alleles at a much higher rate than expected by chance.

That said, if the study is working off the Framingham data, I do wonder how general a conclusion it is...

Re: Friends are as genetically similar as fourth cousins

#62
How many Americans know any fourth cousins? In the village from which two great grandparents emigrated, I have met some third cousins, some at least twice removed, and here in the US I have met second cousins once removed. For what it's worth, it would take a very sharp eye, and maybe an unduly imaginative one, to spot family resemblances between the third cousins and me.

Re: Friends are as genetically similar as fourth cousins

#64
post #18

Earlier quoted context omitted.

Yep. That's the kind of thing you look up at a young age when you discover you're the recent product of second cousins. Some interesting quotes from the "Cousin Marriage" Wikipedia article: "According to Professor Robin Fox of Rutgers University, it is likely that 80% of all marriages in history may have been between second cousins or closer." "Worldwide, more than 10% of marriages is between first and second cousins…

Einsten, Darwin, and Giuliani all married their first cousins, from what I understand.

Well Darwin had 10 children, but only 9 grandchildren. So maybe it didn't turn out so well. Not from a personal or moral perspective mind, just from strictly Darwinian perspective.

Re: Friends are as genetically similar as fourth cousins

#65
post #24

Earlier quoted context omitted.

That's what I use. 2nd uncle, 2nd grand aunt Fun fact: in Russian a first cousin is a 2nd Brother/Sister, a 2nd cousin is a 3rd Brother/Sister and so on.

That makes a lot of sense! The distinction between sibling and nth cousin is basically arbitrary. (Although obviously there is logic in making the distinction as well as in omitting it.)

Arbitrary? You have the same parents with sibling; with cousin you share only one of the two pairs of grandparents.

Re: Friends are as genetically similar as fourth cousins

#66
post #24
post #15

Earlier quoted context omitted.

I get mad at people who think sons of first-cousins are second-cousins all the time -- and, frankly, almost everyone I know think this way. I'm glad you linked to this Wikipedia article that proves I'm not mad into thinking there is a simple logic pattern that can be applied to cousinship. However, this "once removed" notation is crazy. Why not second-uncle for parents of second-cousins and so on?

That's what I use. 2nd uncle, 2nd grand aunt Fun fact: in Russian a first cousin is a 2nd Brother/Sister, a 2nd cousin is a 3rd Brother/Sister and so on.

No, you don't. You don't call a son of your first-cousin your second-cousin. You call him a second nephew I think.

Re: Friends are as genetically similar as fourth cousins

#67
post #3

In case you were also wondering what a "fourth cousin" was, someone who shares a pair of great-great-great grandparents[0]. Wikipedia has a great set of diagrams[1] in case you're also confused about first, second, or third cousins. I figure through induction you can presume any nth and nth removed from that page (I foolishly thought 3rd was where people arbitrarily stopped keeping count....) [0] https://www.referenc…

Let's calculate. I have a pair parents, 2 pairs grandparents, 4 pairs of great grandparents, 8 pairs great-great grandparents, and 16 pairs great-great-great grandparents.

How to estimate the number of fourth cousins?

Re: Friends are as genetically similar as fourth cousins

#68
post #62

How many Americans know any fourth cousins? In the village from which two great grandparents emigrated, I have met some third cousins, some at least twice removed, and here in the US I have met second cousins once removed. For what it's worth, it would take a very sharp eye, and maybe an unduly imaginative one, to spot family resemblances between the third cousins and me.

I know plenty, due to both an active family reunion group and due to genealogical research. It can be pretty fun learning about your ancestors.

Re: Friends are as genetically similar as fourth cousins

#69
post #18
post #16

Earlier quoted context omitted.

Really not an issue with second cousins. Second cousins are genetically different enough that issues with the children are just barely more common in non-related couples.

Yep. That's the kind of thing you look up at a young age when you discover you're the recent product of second cousins. Some interesting quotes from the "Cousin Marriage" Wikipedia article: "According to Professor Robin Fox of Rutgers University, it is likely that 80% of all marriages in history may have been between second cousins or closer." "Worldwide, more than 10% of marriages is between first and second cousins…

A dude with whom I went to elementary school married his first cousin here in USA. This was in a red/"statute bans" state by the map at your link, but I never heard they had any problems from it.

Re: Friends are as genetically similar as fourth cousins

#70
post #24
post #15

Earlier quoted context omitted.

I get mad at people who think sons of first-cousins are second-cousins all the time -- and, frankly, almost everyone I know think this way. I'm glad you linked to this Wikipedia article that proves I'm not mad into thinking there is a simple logic pattern that can be applied to cousinship. However, this "once removed" notation is crazy. Why not second-uncle for parents of second-cousins and so on?

That's what I use. 2nd uncle, 2nd grand aunt Fun fact: in Russian a first cousin is a 2nd Brother/Sister, a 2nd cousin is a 3rd Brother/Sister and so on.

Thank you for being sane.

Russians are decent people, it seems. Is the 2nd-uncle terminology widespread in Russia too?

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