Suggestions for improving the African breakdown on AncestryDNA

In previous blog posts I have demonstrated how the current African breakdown on AncestryDNA can be very insightful to gain a greater understanding of the regional African roots for people across the Afro-Diaspora as well as actual Africans themselves. Despite several shortcomings as well as the continued need for correct interpretation. My survey findings on a group level have still been reasonably in line with either historical plausibility or actual verifiable genealogy.

A new version of AncestryDNA’s Ethnicity Estimates has been provided gradually (and quietly..) to a subset of Ancestry’s customers for at least since April 2018. I do not have all the needed information in place yet to make a proper assessment. Therefore I reserve my final judgment on this intended update for later. However in this blog post I will discuss some suggestions on how to improve on the current African breakdown hopefully ensuring that Ancestry’s update will be a step forward and not a step backwards. Below a short summary of these suggestions. If you continue reading I will provide more details.

  1. Maintain current coherency of African breakdown and improve by creating less overlapping and more predictive regions
  2. Add more historically relevant African samples to Ancestry’s Reference Panel. In particular from Angola, Burkina Faso, Guinea Bissau/Conakry, Liberia, Madagascar, Mozambique and Sierra Leone.
  3. Create new regions and/or migrations centered around these historically relevant samples.
  4. Bring back the continental breakdown display (subtotals specified for each continent)
  5. Create new African “migrations”, a.k.a. genetic communities. In particular for Nigeria & Ghana, as sufficient customer samples may already exist.
  6. Mention the “aggregate ethnicity estimates” for each migration/genetic community.
  7. Enable the Ethnicity Estimate Comparison feature for all customers and not just USA-based smartphone users.
  8. Show ethnicity/admixture of shared DNA segments with your matches.
  9. Avoid misleading labeling of ancestral regions. Providing a false sense of accuracy.

Updated results for a Nigerian (Bini, Itsekiri, Urhobo & Isoko)

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NAIJA updatea

Even when these are only individual results this outcome for an actual Nigerian could possibly imply that also for other people of (southern) Nigerian descent Ancestry’s update may lead to a substantial decrease of “Nigeria” amounts. While the “Benin/Togo” as well as the “Cameroon, Congo, and Southern Bantu Peoples” regional scores may drastically increase. Undoing the imperfect yet still reasonably predictive accuracy of the “Nigeria” region in the current set-up. See also: Nigerian AncestryDNA results.

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Update: Afro-Diasporan AncestryDNA Survey (part 1)

In 2013 AncestryDNA updated their Ethnicity Estimates to include a detailed breakdown of West African DNA. Pioneering when compared with other DNA testing companies. Soon afterwards I started collecting AncestryDNA results in an online spreadsheet in order to conduct a survey of the African regional scores being reported by AncestryDNA. At first only for people of the Afro-Diaspora and later on also among Africans. My main research goal has always been to establish how much the AncestryDNA results on an aggregated group level can already (despite limitations of sample size and other shortcomings) be correlated with whatever is known about the documented regional African roots for each nationality. As well as to improve correct interpretation of personal results.

In May 2016 I published my first summary of my Afro-Diasporan survey findings based on 707 results for 7 nationalities (see this blog post). My survey has been ongoing ever since. Right now an update of AncestryDNA’s Ethnicity Estimates seems even more imminent than it was in 2016 (when it was canceled in the beta phase). So that’s why I will yet again provide a “final” overview of my survey findings 😉 . Mainly based on 1,264 results for people from 8 nationalities. Although the total number of results and nationalities in my survey is even greater.

A major addition is the inclusion of 45 Brazilian results. Their predominant Central African profiles (as measured by both “Southeastern Bantu” and “Cameroon/Congo”) are quite striking when compared with my other sample groups. This outcome reinforces how the African breakdown on AncestryDNA has been reasonably in alignment with historically documented origins of the Afro-Diaspora. Unlike any other DNA testing platform I’m aware of and therefore not to be lightly dismissed despite inherent imperfections.

In the second part of this blogseries I will also provide an overview of the non-African regions (Amerindian, Asian, Pacific etc.) being reported for Afro-Diasporans. As well as a more detailed analysis of their European breakdown.

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This frequency of regions being ranked #1 (regions with the highest amount in the African breakdown) is perhaps the best indicator of which distinct African lineages may have been preserved the most among my sample groups.”

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Chart 1 (click to enlarge)

Afro piechartsa

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