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From: "David Faux" <>
Subject: Re: [DNA] X chromosome ancestry testing: Selecting the rightcandidate
Date: Mon, 12 Jan 2009 10:02:07 -0800
References: <ea3bd9560901072119saabd345j86e44e79424edc02@mail.gmail.com>
In-Reply-To: <ea3bd9560901072119saabd345j86e44e79424edc02@mail.gmail.com>


List:

In a posting to his blog today, Blaine Bettinger has provided additional
information to his fan charts. He now shows the percentage contribution of
each ancestor to the X chromosome. These charts (including one that can be
linked to genealogical number systems) join those of Jim Turner recently
posted here as useful tools to those of us struggling with X research.

The inheritance pattern on this chromosome is so complicated that the only
way to understand what is likely to have come down to you and from whom is
to view things graphically - these charts really help.

http://www.thegeneticgenealogist.com/2009/01/12/more-x-chromosome-charts/

Since 1975 I have spent countless time and resources focusing on the Young
family of Germany, the Mohawk Valley NY, and the Grand River Ontario
Canada. I expect that the reason is that this family holds my deepest
roots in North America. I have a large database and a website devoted to
this family. Little did I realize until now how genetically close my
uncles are to this family - even though Hannah (Young) Dawson was their
great grandmother. She "donated" 50% of the content of their X. Since
Hannah's parents were first cousins the link is even closer (I am fortunate
enough to know her father's Y haplogroup, U152; and her mother's mtDNA
haplogroup, J*; thanks to testing of cousins). So not only does testing my
uncle potentially bring me closest to my Native American ancestry, but also
to my Loyalist German and Swiss ancestors. It is amazing how little I knew
of the X chromosome only a couple of months ago (except in relation to
disease, pathology or medical exceptionalities of one sort or another)
- virtually nothing in relation to genealogy. Perhaps others had also
assumed that it was little different from any of the 22 autosomes.

Ok, now I need to sit myself down and make an air tight case that this
testing is mandatory, despite having retired only a few days ago......

David K. Faux.


On 1/7/09, David Faux <> wrote:
>
> List:
>
> After tapping out Y-DNA and mtDNA testing, and learning more or less all
> (to this point) that the information can tell me (until the dating "issue"
> is better resolved), it seems that shifting gears toward autosomal and X
> chromosome testing is the logical alternative.
>
> After spending a great deal of time documenting Native American ancestors
> the question is whether DNA testing of any sort can assist. Since the paper
> trail is so detailed, why bother? In two words, "cross validation".
>
> Unfortunately the mtDNA line dead ended before 1900. The YDNA lineage
> poses problems in finding a suitable candidate that can be securely linked
> to either he Hill or Green lines. At some point testing of candidates at
> Tyendinaga, Ontario may be undertaken since in this location all
> individuals of these surnames are presumably descendants (assuming no
> unrecorded adoptions and npes).
>
> Testing of myself and various relatives with autosomal DNA via DNAPrint and
> DNATribes has provided data for consideration, but the results of testing
> with the former test have provided small percentages of either Native
> American or East Asian. Still, this seems rather non-specfic, and the
> concerns surrounding the validity of the data yields unsatisfactory
> findings. All of this rather pales in comparison with the one milltion to a
> half million markers available via the new chip technology. The question
> is, can this new technology overcome the obstacles noted above?
>
> Fortunately, in terms of minority ancestry testing, there is good news and
> bad news. The good news is that our family has a wide variety documentary
> sources pertaining to our Six Nations ancestors going back from a birth in
> 1747, five generations into the 1600s. The bad news is that for me, that
> means that this ancestor has made a .004% (1/256) contribution to my
> genome. Hence there is unlikely to be more than a "trace" of this
> non-European lineage. There are family members who, due to being the
> youngest child of the youngest child, are 5 generations removed from the NA
> ancestor, whereas I am 8 generations. Hence there would be a 1/64 or 2%
> genomic contribution. There is every possibility that this would be more
> substantial due to the vagaries of recombination at each meiosis, or could
> in fact be zero or undetectible. The Finonacci series to the rescue.
>
> The X inheritance is like nothing else in genetics. For example, of 128
> ancestors at the 7th generation, only 21 have the opportunity to make any
> sort of contribution. For example, if you are a male, your father made a
> zero contribution since you obtained your Y from him, and your X from your
> mother. The mtDNA ancestor will make a 1/64 contribution at the 7th
> generation and the mother's father's mother's father's mother's father's
> mother will make a 1/8 contribution. By some quirk of fate this woman at
> the top of the fan chart created by Blaine Bettinger:
>
>
> http://www.thegeneticgenealogist.com/2008/12/21/unlocking-the-genealogical-secrets-of-the-x-chromosome/
>
> is my Native American ancestor. The upshot is that despite my low (under
> the radar) autosomal link to this woman, she made a 1/16 contribution to my
> X genome. What is interesting is that my mother's brothers (one remains)
> have a 1/8 contribution. I always thought that the zig zag back and forth
> between male and female gave me a lesser tie to my ancestor, but the
> opposite is correct.
>
> Thanks to Anders and the browser at decodeme, we have determined that the
> largest block on my X which matches anyone in the 51 groups of the Human
> Genome Diversity Panel (worldwide) is 364 SNPs (circa 5 Mb haploblock), with
> a perfect match to a Xibo tribesman of Manchuria in northeast China, and the
> only other close match is to a Yakut, and there is a secondary match to a
> Yakut within this block. Manchuria (original home of the Xibo) and Lake
> Baikal (original home of the Yakut) are considered to be the "home" of
> Native Americans before the migration(s) beginning circa 15 KBP.
>
> All of the high matches (6 or more "high matching" regions) are northern
> East Asian (Xibo, Daur, Miao, She, Tujia), Native American (Pima, Suri),
> West Asian (Hazara, Balochi), and European (Sardinian, Italian, Tuscan).
> The Uyghur individual with 11 "high matching" regions is by far the closest
> match on the X. This is odd, since there is no or low matches to all
> northern Europeans (my primary background) except one person who is Colonial
> American.
>
> Now the decision, to test my uncle, or not, since decodeme offers "more" in
> relation to anything concerning the X chromosome (and the browser is
> excellent). How much more information would this provide. As an "RP"
> (retired person) I can no longer test anyone "just because".
>
> Perhaps those of you considering what the X can or cannot tell you about
> your ancestry might want to fill in the fan charts and see whose DNA is
> likely to be represented on this chromosome. Recall though that, as Ander's
> (Norwegian ancestry) match to a Mongol and Pima shows, interpretation is not
> necessarily straightforward. At this point, being as objective as possible,
> my Xibo and Yakut matches may be interesting distractors - only time will
> tell. At some point individual European ancestors may be identified or
> recognized by their signature on the X - I don't see this as in any way a
> pipe dream - just something that awaits further developments.
>
> David K. Faux.
>


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