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loisrp
07-23-2016, 09:08 AM
I know 23AndMe provides X chromosome ethnicity analysis. Is there any other way to get this done, whether amateur or otherwise?

AJL
07-23-2016, 07:08 PM
The Gedmatch oracles, using a by-chromosome analysis, unfortunately do not include the X.

You may however be able to use some of the R-based offline oracles and feed just your X in there to see what comes up.

tejus
11-07-2016, 06:33 AM
The Gedmatch oracles, using a by-chromosome analysis, unfortunately do not include the X.

C J Wyatt III
11-08-2016, 07:50 AM
The X-chromosome is just not suited for admixture/ethnicity analysis. I've been doing some work with the X-chromosome recently and I think that I can demonstrate a big problem.

Here is an exercise for you to try. Run a 'one-to-many' for a kit on GEDmatch with the default parameters. Click on the downward arrowhead for the 'largest cM' column in the X-DNA grouping to sort. Skip down the list to get past the kits that are closely related to your kit. I would get down to where kits are showing a generations of around 7.0 or so to MRCA. Click on the 'X' to get the 'X one-to-many' comparison. You may need to change the parameters to 500 SNP's to get a segment to show up. On the one to many GM seems to use 500 SNP's but when you go for the confirming 'one-to-one', the parameter for SNP's is getting 700 plugged in. Anyhow save the matching segment data and skip down and run another one. After doing a few you should start getting some triangulations going. By the time you do a dozen or two, you are going to find some serious triangulations going in several areas. What we are finding is that there is some major common ancestry within the past seven or eight generations revealed by the X-DNA analysis. Most everyone will get these results, so to me it is real clear that the X-DNA is not a good path to doing admixture.

I will explain further in the morning.

Jack Wyatt