X chromosome ancestry testing: Selecting the right candidate
I posted this to Rootsweb, but it occurs that some here might also be interested in exploring the information written on the X chromosome.
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:
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
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.
Thanks for the links to the inheritance graphics. On the graphic for males, I was struck by the consistent reading on the direct female line. That would make X testing a good adjunct to mtDNA results, to further prove relatedness between identical or near matches on mtDNA.
I wish I could afford one of the genome scans but I frittered away my testing dollars on family autosomal and X STR's from DNAF/FTDNA. Sigh. Perhaps the New Year will bring more disposable income and refined offerings from the scanners.
Hope you can find a way to get tested, I certainly do not regret a penny spent with decodeme and 23andme. I would have to think twice now. There is a downside to being retired - the word "budget" actually takes on a personal meaning. I expect I will have to go cap in hand to family members to ask for a "contribution" in order to get my uncle tested. I have never done that before - I lost track a long time ago of the number of people for whom I had "taken care of" the testing for everything imaginable.
I have a close FGS match who has one extra mutation but we have an ancestral spot of our mtDNA ancestors of near Bantry Bay in Cork c. 1837-41.. we match on the Coding region exactly..His sisters and my sister and I share many many markers on our X profiles..
however we do NOT share the X haploblock at DXS 10074-10075-10079 nor do we share the mini block at DXS 10066-67-68.
I DO however share one of my X blocks with one person and the other one with another person.. he is currently testing another relative as am I..we have shared know names
They are minimal in expense at FTDNA and are a good starting point and Thomas Krahn has that interactive database at DNA-FP..there are currently 518 users with datasets displayed there..(Which is free)
If everyone who could not currently afford 23and me who has tested and has a sample at FTDA tested those markers it would be only about $50-60 with a free interactive database that has e-mails attached..
But maybe I do not understand the relevance of the whole genome study?
Many of us have done most of it in bits and pieces..
FGS, Y lines for every ancestor we can find..X and at markers for siblings...
I only have the one sister but I did my son who shares one block of course..
Tom has done a PACK of siblings..bless him..
all are welcome
I plan to be much more focused on finding matches with testing I have done already..saving my $$ to test more male relatives..
This thread caught my attention
I am awaiting FGS. After that I, yet another RP, will have come close to exhausting my play money. However, I could always afford $60-70 a pop.
I am anticipating more mysteries await me when my FGS returns. My mother was born on an island. Her family's roots are allegedly nearly 400 years old on that island. But the paper trail is virtually zip. A fair number of members of the purported families of my mother, my grandmother, and my great grandmother have taken various levels of dna testing, y and mt. I don't know about X.
I don't anticipate any Native American ancestry, although there is a theoretical possibility because of the alleged presence of Native American ancestry in a family that may be related from the island (who were Sarawak).
Assuming that there is no Native American ancestry, would X testing provide any information that I might be able to use to unravel the tightly interwoven threads of my mother's ancestry despite the absence of a paper trail before 1825? If so, I did not see where that option was available to me through FT DNA except in relation to Native American ancestry. Is there an option at FT DNA? I do not mean to denigrate anyone else, but FT DNA has gained a certain level of trust and respect from me that is not easily won.
The X markers are available at Family Tree DNA..with a fee of $9.50 to "prepare" this sample the X haploblocks at FTDNA such as the 3 marker at DXS 10074-10075-10079 and the 4 markers at DXS 10066-67-68-69 is less than $60..
You can then put the results at Thomas Krahn's database at DNA -Fingerprint.. here : http://www.dna-fingerprint.com
If you match someone it is interactive and you can then email them..if you have a match fine..if not you are not out many hundreds of more $$..
Right now between my sister and I we have 3 blocks..2 from mother( separate ones) and one from Dad..Since they are X markers you know where you inherit them from..
if enough people did that it would be very helpful..
I currently have 2 matches on one haploblock and 5 matches on the other..the 3rd haploblock is the one that would have come from Dad and that one of course there are no matches on..since I do not know who my Father's father was that one is very important..
But that does not mean I would have necessarily had a match at 23andMe or elsewhere..
"Once we have a useful number of participants in our database, this will
be without a doubt a helpful tool to explore heritage in a mixed
male-female-male-female etc. line. So even if I don't want to make too
much advertising on this list for my own company, I would strongly
recommend to just test those three linked markers from the Szibor paper
(DXS10074 / DXS10075 / DXS10079) for as many people as possible. I also
recommend to connect our X haplotype observations with the male Y
haplogroups, because if the paternal line comes from one region of the
world, it is most likely, that the female partner will also come from
the same geographical region. This would allow us to establish the X
haplogroup map more quickly and the erroreous designations will soon be
averaged out if the sample number increases."
and there is an earlier thread here on the markers..
"Testing DYX 10074-10075 and 10079" or something like that..he also told me the "Other " Haploblock was a lesser one ..
if I find the quote from him on that one I will post that also..
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