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Archiver > GENEALOGY-DNA > 2009-12 > 1260731990


From: "Tim Janzen" <>
Subject: Re: [DNA] R-U152 and R-L21 on the European Continent
Date: Sun, 13 Dec 2009 11:19:50 -0800
In-Reply-To: <4B25282D.8030908@san.rr.com>


Dear Al,
Yes, for the "24 Slow" option, I throw away the "43 non-slowest"
mutating markers. Bear in mind that 17 of these markers are discarded at
the onset because they are multi-copy markers. We discussed the rationale
for this on the list 1½ years ago when Ken and I were first developing
intraclade and interclade TMRCA estimator programs in Excel. The other 26
markers are thrown away simply because their variance is saturated (or at
least partially saturated) when you are looking at TMRCA estimates for old
haplogroups and subclades. You can retain all 67 markers in intraclade and
interclade TMRCA calculations and this is doesn’t create significant
problems when calculating TMRCA estimates for young subclades. However,
retaining all 67 markers for interclade TMRCA estimates for old haplogroups
and subclades creates the same problem that including all of the 50
single-copy markers does in that the interclade TMRCA estimates are
consistently too low for old haplogroups and subclades. I haven’t been
reporting to the list any interclade TMRCA estimates using 67 markers for
about 1½ years because of this problem. For comparison purposes you might
be interested in knowing that the interclade TMRCA estimate for haplogroups
A and B is 46,848 years when using all 67 markers. This compares to 35,245
years I got for 50 markers. In any case, we all know that 46,848 years is
also lower than the true TMRCA for haplogroups A and B.
The average mutation rate for the remaining 24 markers is .00040.
Zhivotovsky et al (2004) use .00069. The 24 markers in my "24 Slow" option
are listed below.
Sincerely,
Tim

472
578
426
455
454
641
436
490
450
388
594
640
531
617
492
392
568
590
438
537
393
565
487
437

-----Original Message-----
From:
[mailto:] On Behalf Of Al Aburto
Sent: Sunday, December 13, 2009 9:45 AM
To:
Subject: Re: [DNA] R-U152 and R-L21 on the European Continent

Hi Tim,
So for the "right mix" ("sweet spot") we throw away the "43 non-slowest"
mutating markers, giving more sensible TMRCA results. This means the
Y-chromosome, as a whole, having some sort of average mutation rate, is
better represented by these 24 slowest mutating markers. I think I
asked this before, but is your average mutation rate for these 24
slowest markers similar to what Zhivotovsky et al (2004) use?
Al





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