Tracing Ancestry with MtDNA (mitochondrial DNA)

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So the fertilized egg contains a mixture of the father and mother's nuclear DNA and an exact copy of the mother's mtDNA, but none of the father's mtDNA. The result is that mtDNA is passed on only along the maternal line. This means that all of the mtDNA in the cells of a person's body are copies of his or her mother's mtDNA, and all of the mother's mtDNA is a copy of her mother's, and so on. No matter how far back you go, mtDNA is always inherited only from the mother.

If you went back six generations in your own family tree, you'd see that your nuclear DNA is inherited from 32 men and 32 women[1]. Your mtDNA, on the other hand, would have come from only one of those 32 women.
NOVA Online | Neanderthals on Trial | Tracing Ancestry with MtDNA

Joe Mobley
  • Profile picture of the author ThomM
    Does that mean I'm related?
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  • Profile picture of the author seasoned
    OK, based solely on your quote:

    So the fertilized egg contains a mixture of the father and mother's nuclear DNA and an exact copy of the mother's mtDNA, but none of the father's mtDNA. The result is that mtDNA is passed on only along the maternal line. This means that all of the mtDNA in the cells of a person's body are copies of his or her mother's mtDNA, and all of the mother's mtDNA is a copy of her mother's, and so on. No matter how far back you go, mtDNA is always inherited only from the mother.

    If you went back six generations in your own family tree, you'd see that your nuclear DNA is inherited from 32 men and 32 women[1]. Your mtDNA, on the other hand, would have come from only one of those 32 women.
    Do you not see the paradox? If the mtDNA of those 64 people came from one person, then it is impossible to really be true unless the 6 billion came from one. What would otherwise make any one family or collection so unique in itself and yet able to be used as a GENERAL sample?. If 6 billion came from one, then how could it determine anything about you, other than your being potentially a human being? It couldn't even determine you were black, white, asian, etc.. Let alone your lineage. GRANTED some speak of mutations, but mutations are, by their nature, RANDOM.

    Steve
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    • Profile picture of the author Joe Mobley
      Perhaps a peek at that quality link I provided might shed some light on your questions and assumptions.

      Originally Posted by seasoned View Post

      OK, based solely on your quote:
      Which may not be the soundest of wisdom.

      Joe Mobley
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  • Profile picture of the author seasoned
    Well, it is late, so I'll save the rest for tomorrow, but this article goes all over the place. It says, in part:

    "So what about all of the mtDNA of the other women who lived during "Eve's" time? What happened to it? Simply this: Somewhere between now and then, they had female descendants who had only sons (or no children). When this happened, the passing on of their mtDNA halted."

    If you had a 100 quadrillion exact duplicates of a material, like mtDNA, could you pick any one out of the whole and consider it unique? NOPE! So the other women had the same as their mother, and nothing happened. I mean I OBVIOUSLY did NOT inherit mtDNA from my maternal grandmother. So HOW would I get it? This theory says my MOTHER got it from her, and I got it from my mother. My mothers is simply the same as hers.

    They also, as I mentioned several times, talk about mutations:
    "Even though everyone on Earth living today has inherited his or her mtDNA from one person who lived long ago, our mtDNA is not exactly alike. Random mutations have altered the genetic code over the millennia. But these mutations are organized, in a way. For example, let's say that 10,000 years after the most recent common ancestor, one of the mtDNA branches experienced a mutation. From that point on, that line of mtDNA would include that alteration. Another branch might experience a mutation in a different location. "

    Yep, and they noticed a pattern to the RANDOM mutations. And the mutation is different in each family even though families collide, etc...

    I still say that going back so far, I don't see how the can reliably check the mtdna and determine which of these suspects did it so long ago.

    Steve
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