Wednesday, January 30, 2013

23andMe for Newbies: Using 23andMe’s Ancestry Composition Tool

First, Choose "Ancestry Composition" from the menu left side of the 23andMe webpage.

When you first go to this page, you will see a round map illustration with a blue bar graph surrounding it, and a list of percentages on right hand side of page.  

At top of page, there are four pull-down menus:  one saying “Map View”, next saying “Global Resolution”, another with your name, and a fourth saying “Standard Resolution”.

If you check out the “Map View” menu first, you will see that there are three choices:  Map View, Split view, and Chromosome view.  

--Map view is the round map with bar graph, which you see when you first open the page.  It shows you exactly where on the map your ancestors came from.

--Split view is only for those who have had both parents tested; it will show which parent provided which ethnic ancestry. Since I don’t qualify for this feature, I can’t really comment on it.

--Chromosome view (my favorite) shows you a visual representation of 22 pairs of chromsomes plus two X chromsosomes if you are female and one X chromsome if you are male. 

This features shows you the location on each chromosome of your ethnic background, represented by different shades of blue.  For instance, in my case, I have Scandinavian ancestry (dark blue), located on one of the pairs of chromosome 1 and on one of the pairs of chromosome 5.  

This feature will eventually be incredibly helpful when comparing two individuals for genealogy.  For instance, if you have three people showing Native American ancestry on a certain location of chromosome 3, and you have Native American ancestry on that location and also match those individuals, then it’s likely that you all received the Native American ancestry from the same ancestor!  

At the moment, we only have a visual chromosomal representation from 23andMe.  I’m hoping in the future there will also be a numeric representation, or a way to show which of our Relative Finder contacts are matching on a particular segment in the Ancestry Composition view.

The second button called “Global Resolution”  also has three settings, Global Resolution, Regional Resolution and Sub Regional Resolution, the last one showing the most specific information on ethnic ancestry, as it is currently known.

The third button has your name on it.  It’s a pull-down menu that shows every one you  have shared DNA with on 23andMe, those who are in your Genome Sharing list (see menu, left side of page under “Sharing & Community”.

With this feature, it is possible to view the Ancestry Composition of any person who has accepted your invitation to share.

The fourth button “ Standard Estimate”  also has three settings:  Standard, Speculative & Conservative Estimate.   

If I look at the Chromosomal View, Sub Regional Resolution, and Standard Estimate, these are the percentages I get on the right hand side of the page:

99.8%  European

--Northern Europe

16.7% British & Irish
1.8% Scandinavian
0.7% French & German
69.1% Non Specific Northern European (in my case Dutch, Belgian, Swiss, Welsh, Scottish)

--Southern European

0.4% Italian
0.5% Non Specific Southern European (in my case possibly Romanian or Greek)

--10.6% Non Specific European

0.2% Unassigned

This seems to be fairly accurate, from my own genealogical research, but the percentages seem a bit off.  However, when I move to the Speculative Estimate, the percentages seem much more in line with my research:

100% European

--Northern European

48.8% British & Irish
10.2% French & German
4.5% Scandinavian
33.8% Non Specific Northern European (in my case Dutch, Belgian, Swiss, Welsh & Scottish)

--Southern European

1.3% Italian 
0.5% Non Specific Southern European (possibly Romanian or Greek)

less than 0.1% Ashkenazi (can’t explain that one)

0.6% Non Specific European.

Now why aren’t all European regional groups represented, such as Dutch & Scottish?  Partially it is because 23andMe is using information from it’s Ancestry Finder (under Ancestry Labs, menu left side of the webpage).  All populations are not yet represented, or there is not enough data to clearly delineate them.  I’m uncertain whether or not they use other sources, but I would guess that they would. That may be a question that could be posed on one of the forums on 23andMe.

Native American ancestry is clearly shown on 23andMe.  It you have any Native American DNA at all back five generations, it will clearly show up!

Have a great day!


© Betty Tartas  2013

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