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Archiver > GENEALOGY-DNA > 2002-01 > 1011844917


From:
Subject: [DNA] Identical Results (mtDNA, Y-DNA) of Different Haplogroups
Date: Wed, 23 Jan 2002 23:01:57 EST


Although I'm not familiar with the technicalities of Y-DNA sequencing and
haplogroup assignment, I do know that the problem of haplogroup ambiguity can
exist with some mtDNA Hypervarible Region I (HVR-I) sequences. As I
understand it, the 500 or so bases sequenced in HVR-I are not (always) enough
to infer the haplogroup because the motifs for assignment are/can be based on
mutations both outside and within HVR-I. Labs generally sequence HVR-I
because its mutations alone are usually unique enough to correlate with a
specific haplogroup (so testing additional bases would be unnecessary and
expensive). Perhaps the principles/procedures for classifying Y-DNA are
similar.

This subject is of interest to me because my own mtDNA HVR-I sequence
(16126C, 16362C) is ambiguous, in that it could belong to one of several
haplogroups - pre-HV, pre-JT, J (where the mutation at 16069 reversed back to
the control sequence), or T (where the mutation at 16294 reversed back to the
control sequence). Although Oxford Ancestors originally assigned my sequence
to haplogroup J, I learned (after inquiry) that they did so because
assignment to one of their 33 clans ("whenever possible or reasonable") is
their policy. Since my (known) maternal ancestry is English, and all of the
sequence/haplogroup possibilities above point to a middle-eastern origin,
haplogroup J (or "Jasmine") seemed like the most "reasonable" choice (and,
apparently, some past customers have complained (ridiculously enough) upon
finding out that they were not directly descended from one of the fictional
clan mothers!).

In a message dated 1/23/2002 12:58:30 PM Pacific Standard Time,
writes:


> (3)
> the results are not really the same because they are in different
> haplogroups (I don't understand this last argument -- it suggests that there
> are other markers that should have been tested but weren't).
>




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