Thursday, 7 June 2018

Updated "ethnicity" estimates at AncestryDNA

AncestryDNA are starting to roll out updated "ethnicity" reports. The number of reference samples has gone up from 3,000 to 16,000 (a five-fold increase), and there are 17 new Regions (the feature that was formerly known as genetic communities). Ancestry say that they have found "improved ways" to analyse our data:
DNA is made up of strings of four different letters: A, C, G, and T. Our old algorithm looked at one letter at a time, and based on where that letter appeared in your DNA, it decided where that bit of DNA came from. Without getting too technical, our new algorithm reads longer stretches of your DNA at once, making it easier to identify regions of the world where you ancestor once roamed.
You can see the updated FAQs here.

I have updated reports on my own Ancestry account and the accounts for my parents but not everyone is yet seeing the new reports. Apparently the updates are in the test phase until 12th June. Here are the updated reports for me and my parents. It may be that these reports will be updated again once the testing has been completed.

On checking into my account I am given the option to preview my new estimate.


There is a short questionnaire to fill and I can then access my new report:



Here is the updated report for my dad:


Here's the updated report for my mum.


Ancestry have provided some fun answers to common questions. My mum and I have an answer to the question "How do I get my Viking tattoo removed?" (Fortunately this was not something I had ever considered doing on the strength of my 1% Scandinavian assignment!)


My dad has an answer about the loss of his Iberian ancestry. (Previously 10% of his genetic ancestry was matched to the Iberian peninsula.)

If you accept the new estimate it becomes your default. The page showing the differences between the old and new version is then no longer available so you might want to save a screenshot for reference. Note too that although the Regions are listed as Migrations in the preview, they revert to their previous status when you accept the new report.

Conclusion
All my ancestors that I can trace in the last five or six generations are from England with the exception of one great-great-great grandfather on my dad's side from Scotland and one great-great-great grandmother on my mum's side from Ireland. Our updated reports are now a much better reflection of our recent genetic ancestry, though the 10% Norwegian and 3% Scandinavian in my dad's results appear to be an anomaly. I hope that, when the results are rolled out to all customers, Ancestry will publish an updated white paper with details of the new methodology and the new reference populations. I presume the massive percentage increase in the amount of our ancestry assigned to England and Wales is a reflection of the large number of people from these countries who are now in the AncestryDNA database I am sure that we can look forward to further refinements in the future.

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