Board 8 > Does anyone know anything about DNA?

(+) Yeah! (+)

My mom has insisted for years that she's part Native American. I said she's not. She spent money on multiple DNA tests that all said she's 100% white from Britain, the Netherlands, and so on. She finally got angry at this and without telling me got a mitochondrial DNA test that finally said she's 0.1% Native American (that's the actual number the test gave). Is it possible that Native American DNA could be gone from her DNA but still exist mitochondrially?
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Do you have loyalty or royalty inside your DNA?
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https://www.youtube.com/watch?v=LvAsHTn3pbM
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uh....gonna say I don't think so?

I thought Mitochondrion DNA changed so little that wouldn't really happen.
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Kinda sounds like your mom just doesn't like admitting she's wrong.
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.1% is probably within the margin of error.
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Based on just my high school AP Biology-level understanding:

Mitochondrial DNA is only passed down from the mother, so mitochondrial DNA tests aren't actually useful for this sort of thing.

Like, if your mitochondrial DNA is "25% Native American", that doesn't mean you're 25% Native American. It means your mother, your mother's mother, your mother's mother's mother, etc would each theoretically have "25% Native American" mitochondrial DNA.

So I'm pretty sure that all .1% Native American actually means on a mitochondrial DNA test is that her maternal ancestry is NOT Native American (since only .1% of it matches). It doesn't prove or disprove that there's some Native American from one of her many, many other ancestors, so you should probably just listen to the regular DNA test results.

deep down aren't we all at least 0.1% Native American
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LambdaPublic posted...

Based on just my high school AP Biology-level understanding:

Mitochondrial DNA is only passed down from the mother, so mitochondrial DNA tests aren't actually useful for this sort of thing.

Like, if your mitochondrial DNA is "25% Native American", that doesn't mean you're 25% Native American. It means your mother, your mother's mother, your mother's mother's mother, etc would each theoretically have "25% Native American" mitochondrial DNA.

So I'm pretty sure that all .1% Native American actually means on a mitochondrial DNA test is that her maternal ancestry is NOT Native American (since only .1% of it matches). It doesn't prove or disprove that there's some Native American from one of her many, many other ancestors, so you should probably just listen to the regular DNA test results.

All she needs is one person in her ancestry to have been Native American, no matter how far back, to keep talking about this forever.
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Ask her if she would call herself black if she had one black ancestor ten generations back
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Mitochondrial DNA doesn't reproduce with the normal genome, so it's not like her "native american" DNA could have somehow migrated to it. I'm not really sure of the methodology used here but 0.1% sequence similarity or whatever this is is probably unimportant.

That said for the sake of an argument, it's definitely possible to have had a native american ancestor and their genes just migrate naturally out their ancestors over time. Should take more than a few generations but if you think about it, first ancestor is 50% and it halves each generation until it's basically nothing. If we're talking recent though like five generations back then no way, should still be like 3%.
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WazzupGenius00 posted...

Ask her if she would call herself black if she had one black ancestor ten generations back

Without asking I know the answer is yes.
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HeroDelTiempo17 posted...

That said for the sake of an argument, it's definitely possible to have had a native american ancestor and their genes just migrate naturally out their ancestors over time. Should take more than a few generations but if you think about it, first ancestor is 50% and it halves each generation until it's basically nothing. If we're talking recent though like five generations back then no way, should still be like 3%.

It's still very unlikely due to crossover.

Like...26 chromosomes, but even within one chromosome they will cross in random places:

https://en.wikipedia.org/wiki/Chromosomal_crossover

There's still a probability element to all of this, granted, but it should be something like...

parent: 50%
grandparent: 25%
great grandparent: 12.5%
gg grandparent: 6.25%
ggg grandparent: 3.125%

Hmm...assuming she was born in 1950...
grandparent 1925
g grandparent 1900
gg grandparent 1875
ggg grandparent 1850
gggg grandparent 1825
ggggg grandparent 1800
gggggg grandparent 1775
ggggggg grandparent 1750
gggggggg grandparent 1725
ggggggggg grandparent 1700
gggggggggg grandparent 1675
ggggggggggg grandparent 1650
gggggggggggg grandparent 1625

(And realistically that's about as far back as you can go, cause that would require like...one of the first settlers from Jamestown Virginia.)

That said, going back that far would actually produce a 0.006% on average DNA relationship. Given that these DNA tests don't seem to get more accurate than 0.1%, and the process of gene swapping is random anyway so it could be LESS than 0.006%...yes, she could be 1/16384 Native American and it wouldn't show up on the test.

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The mitochondrial test, however, doesn't show shit. Mitochondrial DNA is only passed down from your mother, meaning your mother has basically the same Mitochondrial DNA as you, and basically the same Mitochondrial DNA as her mother, and her grandmother, and her great grandmother and so on. If it's showing 99% European, then that just means that one side of her family (her unbroken matriarchal line) was definitely European, no questions asked.
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Oh wait, what am I doing? I came to this topic to post this:

https://www.youtube.com/watch?v=f8FAJXPBdOg&t=3m10s
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metroid composite posted...

Oh wait, what am I doing? I came to this topic to post this:

https://www.youtube.com/watch?v=f8FAJXPBdOg&t=3m10s

this is not what i expected, but now that i've seen it its exactly what i wanted
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metroid composite posted...

HeroDelTiempo17 posted...

That said for the sake of an argument, it's definitely possible to have had a native american ancestor and their genes just migrate naturally out their ancestors over time. Should take more than a few generations but if you think about it, first ancestor is 50% and it halves each generation until it's basically nothing. If we're talking recent though like five generations back then no way, should still be like 3%.

It's still very unlikely due to crossover.

Like...26 chromosomes, but even within one chromosome they will cross in random places:

https://en.wikipedia.org/wiki/Chromosomal_crossover

There's still a probability element to all of this, granted, but it should be something like...

parent: 50%
grandparent: 25%
great grandparent: 12.5%
gg grandparent: 6.25%
ggg grandparent: 3.125%

Hmm...assuming she was born in 1950...
grandparent 1925
g grandparent 1900
gg grandparent 1875
ggg grandparent 1850
gggg grandparent 1825
ggggg grandparent 1800
gggggg grandparent 1775
ggggggg grandparent 1750
gggggggg grandparent 1725
ggggggggg grandparent 1700
gggggggggg grandparent 1675
ggggggggggg grandparent 1650
gggggggggggg grandparent 1625

(And realistically that's about as far back as you can go, cause that would require like...one of the first settlers from Jamestown Virginia.)

That said, going back that far would actually produce a 0.006% on average DNA relationship. Given that these DNA tests don't seem to get more accurate than 0.1%, and the process of gene swapping is random anyway so it could be LESS than 0.006%...yes, she could be 1/16384 Native American and it wouldn't show up on the test.

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The mitochondrial test, however, doesn't show shit. Mitochondrial DNA is only passed down from your mother, meaning your mother has basically the same Mitochondrial DNA as you, and basically the same Mitochondrial DNA as her mother, and her grandmother, and her great grandmother and so on. If it's showing 99% European, then that just means that one side of her family (her unbroken matriarchal line) was definitely European, no questions asked.

But then how does the Mito DNA say part Native American?
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metroid composite posted...

There's still a probability element to all of this, granted, but it should be something like...

Well yes, but it's very hard to quantify the effects of genetic drift for one person and their ancestors. It could be the expected value which all we can really guess, but it could also be very strong.

Anagram posted...

But then how does the Mito DNA say part Native American?

Without actually seeing the test, I'm guessing it's testing something like sequence identity. That means 0.1% of the dna matches a native american reference but it doesn't mean that it had to come from a Native American. It's more likely that this is just a very small amount of overlap.
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I guess to explain more, it's looking at the DNA code (GCAT) and comparing them. Long stretches of exact same code combinations are unlikely to be unrelated due to chance. This is how paternity tests work, they find a bunch of repeated sequences in the father and the son. But because this match is so small and because of how mitochondria dna gets inherited, this is probably one of those random chance scenarios.
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Lemme guess, Cherokee?

https://timeline.com/part-cherokee-elizabeth-warren-cf6be035967e

Interesting read on why tribal ancestry is so commonly claimed by southern white people
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She doesn't know what tribe she descends from (if she did), she just wants to have something in her history more interesting than Dutch.
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I need to get one of those ancestry tests done one of these days. I know I've got Dutch on my mom's side and Irish on my dad's side, but I don't know what else could be in there because my dad never knew his biological father.
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