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Archiver > GENEALOGY-DNA > 2010-02 > 1266716288


From: "Alister John Marsh" <>
Subject: Re: [DNA] TMRCA of R1b1b2s to King Tut?.
Date: Sun, 21 Feb 2010 14:38:08 +1300
References: <mailman.5787.1266597968.2099.genealogy-dna@rootsweb.com><7B3ED479CB324BD7925ACA7EB65A99C7@anatoldesktop><SNT131-ds20D5FD667AA954080F09D5BC450@phx.gbl><E89646B1EE5B47C980746A6D567A0A8A@RichardNW>
In-Reply-To: <E89646B1EE5B47C980746A6D567A0A8A@RichardNW>


Rich,

You said
>>>>>>>
Wasn't that whole "King Tut might have been U152" thing based on the
mistaken idea that he had 393=9? Since it turns out Tut actually has 393=13,

U152 doesn't seem any more likely than any other variety of R1b1b2.
<<<<<<<

MY MISTAKE: Yes! I started this thread hastily before leaving for a few
days away, and I was in error about a few things.

I think the U152 comment was made in reference to another Egyptian who had
the rare DYS393=9 who wasn't king Tut. It would never the less be
interesting to know more about his haplotype, and know more about his modern
day matches.

IF TUT IS R1B1B2, WHICH SUBCLADE?: As Anatole noted, most of the main R1b
subclades U106, P312, U152, are old enough for Tut to have been part of
them, but realistically, we can't know from haplotype which if any he
belonged to.

CLOSEST MODERN MATCHES TO TUT: I was interested in the closest modern
matches to Tut, Y-Search ER7RQ. The nearest match Weaver QG7FB is 16/17
match. I note however that the rare dual peak markers DYS19=8/14,
DYS437=9/14 are not included in the Y-Search ID ER7RQ. How do you deal with
rare dual peaks when estimating TMRCA?

If you ignore the dual peaks, I would "guess" that a 16/17 match would
normally be estimated (50% probability) to be a match between individuals
separated by about 30 to 40 birth events. (I have not done this calculation,
just roughly extrapolated from other similar cases.) Given that Tut lived
about 120 generations ago, they are clearly not that closely related.
Realistically, we can't learn much from the TMRCA calculations, other than
to say that generally a 16/17 match "could" be separated by 120 or more
generations, as proved by the evidence of this case. I suppose that is
confirmation of something, as unhelpful as it seems.

It is interesting that Tut's closer range of matches are generally from the
British Isles neighbourhood, but that could be simply that the area has been
most highly DNA tested.

If a line from Tut's grandfather with 17 markers tested had about one
mutation in say 30 to 40 generations, one would typically expect I would
guess about 3 or 4 mutations down to the present.

ARE THE DUAL PEAKS REPORTED LIKELY TO BE REAL? : I wondered what the
significance of these dual peaks might be. Dual peaks at DYS19 are very
rare, and at DYS437 seem non existent in living people as far as I can tell.
Could it be that coincidently these second peaks of very rare values could
be interference from some sections of autosomal DNA? Or is contamination
most likely?

DUAL PEAKS AS DYS19= 8/14: On Y-Search, As far as I can see DYS19= 8 is rare
or non existent in R1b. The range on the R1b project is 12, 13, 14, 15, 16,
with 14 being very dominant. Based on this, it would seem a value of 8
would signal a "very" rare event. If it was common in antiquity, a value of
8 does not look to have survived in numbers, even in Pharaohs who
occasionally had multiple wives.

I wondered how dual peaks might occur. I supposed that if a person had dual
peaks a section of the Y-DNA may have been duplicated, meaning the peaks
should be repeats of the same value initially. I looked to see how common
peaks of considerably different values might have occurred. In the R1b
project, I can only see one result with dual peaks, a Parker with 14/15. A
score of 14/15 looked plausible to me. If a dual peak of 14/14 had
initially occurred, it is plausible that within the time span of having a
few hundred descendants, one peak might have mutated, giving 14/15.

But if Tut's ancestor had a duplication of a section of his DNA, perhaps to
14/14, it would seem that in normal circumstances, assuming 1 step mutations
are much more common, it would take a tree with probably many thousands of
descendants to reach 8/14 in a descendant. If a tree had so many
descendants, it is curious that so few with multiple values made it to the
present day, let alone with anything like 8/14. If Tut were to be U106,
P312, or U152, his birth would only be a few hundred years from current
predictions of the founding of those clades. That would be say 30
generations from the founding of the clades. Even if it was 100 generations
(3,000 years), it seems a short time to mutate to a dual peak of 14/14, then
mutate 6 steps on one peak to 8/14. When you look at how stable R1b seems
to be at around DYS19=14 (+/- 1 or 2 on rare occasions.) it makes a mutation
to 8, or 8/14 look incredibly rare.

Nothing is impossible (almost), but would Ockham's razor suggest that if Tut
was DYS19=8/14, it likely took hundreds of generations (Thousands of years)
to mutate from probably R1b modal of 14 to 14/14, then mutate on to 8/14?

DUAL PEAKS AT DYS437= 9/14: On Y-Search, the range of marker scores does
not permit an entry of DYS437=9. There are no dual peaks in the R1b
project. I was unable to find any results with dual peaks at this marker on
Y-Search. But in searching the R1b project, I was unable to find any R1bs
with anything less than 14 at this marker. That really surprised me. If
R1b was sufficiently stable at values above DYS437= 14, it makes a peak of 9
look exceedingly rare.

Does anyone know if DYS19 and DYS437 are nearby each other on the DNA? If
Tut's ancestor had a section of DNA duplicated, could the stretch have been
long enough to have covered both of these STRs? Are there any other of the
17 STRs tested which are between DYS19 and DYS437? If there were, perhaps
they should have dual peaks also?

So what are the odds, a dual peak at DYS437 is an incredibly rare event not
yet seen in living R1bs, or perhaps interference from a similar section of
autosomal DNA, or contamination, or as a result of decay of the DNA?

If Tut really did have both of these very rare double peaks, of very rare
values, does Ockham's razor suggest that Tut's branching off lines to living
R1bs was possibly many thousands of years before Tut lived?

John.







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