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Archiver > GENEALOGY-DNA > 2004-11 > 1101188975


From: "Rolla Queen" <>
Subject: Getting up to speed
Date: Mon, 22 Nov 2004 21:49:39 -0800 (Pacific Standard Time)



I am new to the list, and may be in over my head for the time being, so
humor me. I have
a few basic questions, and so far most of the online documents that try to
explain stuff get way too complicated way too fast. We just started a
surname
YDNA test at FTDNA about 3 months ago and have about 27 participants so far.
I have been trying to decipher and absorb as much as I can to help the other
members of our group understand what we are seeing in the results.

Questions

1) Is there some significance to the selection and order of the 3 groups of
markers in the FTDNA test? To rephrase, why are the first twelve markers
chosen first? Are they more stable over time, slower mutation rates, etc.?
Why not start with the second group of markers?

2) If the first 12 markers are special and better at showing group
affiliation at
the population level, what significance should I read into a rare marker #12
(7%) for DYS392. When I enter this number into the Whit Athey predictor, it
dramatically drops the probability of membership in Haplogroup R1b from
about 95% to 72% for my results.

3) Is there a set of DYS markers and alleles that form the Atlantic and
Western Atlantic Modal Haplotypes? Is this a subset of the 12 marker panel,
or a specific marker sequence in the 12 marker panel? I am still trying to
understand the significance of these groups and membership in these groups.
According to FTDNA, one of our members is likely in the Western Atlantic
Modal Haplotype. In what way is this different from the Atlantic Modal
Haplotype?

4) I seem to see a lot of debate so far on the relative value of mis-matches
in the 12 marker panel versus the remaining markers in the 25 and 37 marker
panels. It seems to me that if there is a relatively constant rate of
mutation in the model, stated as .002 or 1 mutation for every 500
transmission events, then why would a mutation in the 12 marker panel be
weighed or rated more heavily in early screening than any other marker in
the overall scheme of things? Is it not possible to have a 2 marker mismatch
at the 12 marker level, and end up with a 35/37 match at the 37 marker
level? Or does this go against some fundamental assumption or givens about
the markers being chosen?

I hope these questions are not too simplistic - so if I need to go back to
the
woodshed for more learnin' so I can ask better questions, please point me to
the right door.

thanks

Rolla


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