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nodeciapalabras OP t1_iv0ry9n wrote

Reply to comment by angelicism in Why don't we have Neandertal mitochondrial DNA? by nodeciapalabras

>t all (all humans) have the same mitochondrial DNA from this Mitochondrial Eve?

You mean alive humans? If so, we have, the mitocondrial Eve is by definition the mother to dauther common line all the alive human beings have. But the mitocondrial DNA is not exactly the same for everyone since it mutates. Have in mind that mitocondrial Eve is not always the same individual, it can change any time a mother to dauther line ends.

If you mean all the human species, this would be a different concept, since the mitocondrial Eve concept comes from the ALIVE individuals. But you could theorically think about this new concept. You would have to go back so long to get back to the first ancenstor.

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angelicism t1_iv0stsr wrote

Ah so it does mutate. So when Forensic Files says they got an "exact match" it's not necessarily true that one will perfectly match one's mother?

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SweetBasil_ t1_iv1b5ch wrote

On average a mitochondrial sequence will have a single mutation every several hundred years. So exact matches are common if it's within ~20 generations or so.

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angelicism t1_iv1by71 wrote

So matching mitochondrial DNA doesn't actually mean much in the context of forensics then, because you could also match with your 13th cousin 6 times removed and for all you know there are 17 of them in your village?

(I am zero surprised a TV show is wrong about science, by the way.)

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SweetBasil_ t1_iv1d0kn wrote

When you use DNA to match to a suspect, you usually use short tandem repeat (STR) length patterns in nuclear DNA, which change more frequently than nuclear DNA by several orders of magnitude.

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angelicism t1_iv1g8e2 wrote

There are multiple episodes specifically about matching mitochondrial DNA with the suspect's mother, which was my specific question. :)

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SweetBasil_ t1_iv1h3y7 wrote

should definitely get a nice match with a mother, but i wouldn't put anyone on death row based on that alone :)

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