Cousins' Relevance

Genetic genealogy is the application of genetics to traditional genealogy. Genetic genealogy involves the use of genealogical DNA testing to determine the level and type of the genetic relationship between individuals.
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darkerhorse
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Cousins' Relevance

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I have no paternal 1st cousins.

I have one family of paternal 2nd cousins whose mother's mother's mother also was my paternal grandfather's mother.

I think the cousins would have inherited MtDNA from that line (my grandfather's mother's maternal line).

If so, what would be the relevance to me? What could I learn?

The paper trail suggests that line (mother to daughter) was in Sicily since at least the 1700s.
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MarcuccioV
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Re: Cousins' Relevance

Post by MarcuccioV »

darkerhorse wrote: 26 Aug 2022, 00:56 I have no paternal 1st cousins.

I have one family of paternal 2nd cousins whose mother's mother's mother also was my paternal grandfather's mother.

I think the cousins would have inherited MtDNA from that line (my grandfather's mother's maternal line).

If so, what would be the relevance to me? What could I learn?

The paper trail suggests that line (mother to daughter) was in Sicily since at least the 1700s.
Basically their mtDNA history would apply to your grandfather, but he could not pass it forward.

So any info you might gain WILL apply to you as his grandson, just not the mtDNA as it stopped with him. It's still a worthwhile line to pursue. I just wish I was so lucky...
Mark

If you ignore your foundation, your house will eventually collapse...
darkerhorse
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Re: Cousins' Relevance

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I already know the y haplogroup of my paternal grandfather's father, and of my paternal grandmother's father.

In addition, I'm in touch with various cousins, who haven't had DNA tests yet, from whom I could learn the following (if the were tested):

MtDNA haplogroup of my paternal grandfather's mother

MtDNA haplogroup of my paternal grandmother's mother

y haplogroup of my maternal grandfather's father

I also have cousins I know of but I'm not in touch with, from whom I could learn the following (if they were tested):

MtDNA haplogroup of my maternal grandfather's mother

y haplogroup of my maternal grandmother's father

MtDNA haplogroup of my maternal grandmother's mother

To my knowledge, none of these cousins have had DNA testing. Only two of the six unknown haplogroups are for Italian (Sicilian) ancestors. The two known Y haplogroups come from a surname cousin (Sicilian).

How common is it to have most or all of this information?

How complete of a picture would it paint if i learned all eight haplogroups (which is unlikely since my extended family doesn't seem to DNA test)?

Any priorities?
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MarcuccioV
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Re: Cousins' Relevance

Post by MarcuccioV »

darkerhorse wrote: 26 Aug 2022, 04:59 I already know the y haplogroup of my paternal grandfather's father, and of my paternal grandmother's father.

In addition, I'm in touch with various cousins, who haven't had DNA tests yet, from whom I could learn the following (if the were tested):

MtDNA haplogroup of my paternal grandfather's mother

MtDNA haplogroup of my paternal grandmother's mother

y haplogroup of my maternal grandfather's father

I also have cousins I know of but I'm not in touch with, from whom I could learn the following (if they were tested):

MtDNA haplogroup of my maternal grandfather's mother

y haplogroup of my maternal grandmother's father

MtDNA haplogroup of my maternal grandmother's mother

To my knowledge, none of these cousins have had DNA testing. Only two of the six unknown haplogroups are for Italian (Sicilian) ancestors. The two known Y haplogroups come from a surname cousin (Sicilian).

How common is it to have most or all of this information?

How complete of a picture would it paint if i learned all eight haplogroups (which is unlikely since my extended family doesn't seem to DNA test)?

Any priorities?
To know ALL of the haplogroups would be extremely rare and also extremely enlightening. I know ONLY the mtDNA group from my mother's direct line (my Italian half only). Only ONE first cousin has tested (the illegitimate one), but because she is female and her father is my maternal relative, NONE of her haplogroups intersect with mine. Her dad's Y-DNA (same as my grandfather) doesn't go to her since she is XX, with no Y chromosome. Her Dad's mtDNA (same as mine) stops with him as he is male & cannot pass it on. So much depends on the sexes of the cousins as to who gets what. But again, to know them all would be a rarity indeed...
Mark

If you ignore your foundation, your house will eventually collapse...
darkerhorse
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Re: Cousins' Relevance

Post by darkerhorse »

Rare because DNA testing is rare or because I know various cousins who would fit the bill?

I suppose I would learn the MtDNA haplogroup of my maternal grandmother's mother from my own DNA testing. That would make three known haplogroups.
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MarcuccioV
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Re: Cousins' Relevance

Post by MarcuccioV »

darkerhorse wrote: 26 Aug 2022, 14:20 Rare because DNA testing is rare or because I know various cousins who would fit the bill?

I suppose I would learn the MtDNA haplogroup of my maternal grandmother's mother from my own DNA testing. That would make three known haplogroups.
Yes and yes.

Correct.
Mark

If you ignore your foundation, your house will eventually collapse...
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