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Archiver > GENEALOGY-DNA > 2011-03 > 1299860389


From: JimT <>
Subject: Re: [DNA] Interesting mtDNA example
Date: Fri, 11 Mar 2011 08:19:49 -0800


There is someone who matches me exactly in the coding region,
including a mutation that only the two of us have in our haplogroup.
We don't show up as matches to each other because we have a difference
in HVR1. FTDNA's mtDNA matching algorithm leaves a great deal to be
desired.

Jim Turner

> From: Aaron Salles Torres <>
>
> All,
>
> I manage the Fernandes DNA Surname Project, where I also allow the display
> of mtDNA results - as this is an Iberian surname, and in Iberia last names
> are often inherited matrilineally.
>
> If you take a look at our results section (
> http://www.familytreedna.com/public/Fernandes/default.aspx?section=mtresults
> ), you will notice two individuals in the C1 haplogroup, 186136 and 190662.
> 186136 is 190662's son and they both have ordered the FGS test (not
> displayed due to privacy reasons). In any case, you will notice that the son
> has a mutation in the HVR2 panel (204Y) not presented by the mother. This is
> interesting in itself, because if we did not know they were related, we
> would assume there was just "50% chance the MRCA lived 1300 years ago."
>
> This is because - and here is what is more interesting to me - the mother
> does not see the son as a match on the HVR2 panel, nor under the FGS
> results. The son, however, does see the mother as a match under both HVR2
> and FGS. The implication is that if your mtDNA line has remained unchanged
> while a close relative has had a mutation, you will not be aware that the
> individual is so close to you - you will not see them as a match under HVR2
> or beyond.
>
> How often does this happen (a close relative having an "unexpected" mtDNA
> mutation like this) and how many matches are we missing in our genealogical
> explorations due to the way FT DNA displays these results?
>
> I already have had similar problems with Y DNA results, in which two close
> individuals have one mismatch in the 12 marker panel. As there are not many
> individuals outside of the US and Britain who have been tested by FT DNA,
> many international clients happen to have no matches under the 12 marker
> panel. That is discouraging and, for that reason, they do not order further
> tests. When I have caught such cases on ysearch and convinced such
> individuals to test more markers, they were a 65/67 or 66/67 match with
> someone whose profile I managed. This is what I call a false negative. So
> why not show ALL 11 marker matches, whether two individuals are part of the
> same project or not? Same thing seems to apply to mtDNA results: are the
> match displaying standards too strict? Shouldn't it be up to the clients to
> choose which matches they should pursue or not?
>
> Best regards,
> Aaron Torres
>

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