Category Archives: DNA Studies

Final summary: North & East African AncestryDNA results 2013-2018

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Without wanting to rehash things this blog post and following ones will provide a quick recap of my final AncestryDNA survey findings for continental Africans. These results were obtained during 2013-2018 but I had not fully processed all the data up till now. Continuing with my North & East African section. Which I first published on 20 November 2016 when I had only 58 North & East African AncestryDNA results available for my analysis (see this overview). As my survey has been ongoing I have managed to collect a sample group which has now more than doubled in sample size. Consisting of no less than 135 AncestryDNA results of  North & East African persons!  Follow the link below for detailed analysis & new screenshots:

Table 1 (click to enlarge)

Stats (n=135)

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I discontinued this survey after Ancestry’s update in September 2018. Because in my opinion Ancestry’s new version of their ethnicity estimates regrettably has been a downgrade in regards to their African breakdown, overall speaking (see also this blogseries). Which is why I think these “old” results may still be useful and are not obsolete yet. I originally singled out two main implications for Afro-Diasporans which I still stand by.

  1. Careful follow-up research is required to substantiate any DNA results seemingly suggesting East African lineage.
  2. Careful follow-up research is required to substantiate any DNA results seemingly suggesting North African lineage.

Then again my intention is not only to look backwards but also forwards! In particular I believe that this dataset may provide a helpful baseline to compare with 23andme’s newly updated African breakdown (see this overview). Furthermore my findings may also serve as a benchmark for Ancestry’s upcoming update, which hopefully this time will lead to improvement! I find that currently 23andme is much better equipped to detect Northeast African & North African lineage. While also the distinction made for Southeastern African lineage on 23andme is particularly useful for Afro-Diasporans seeking to validate seemingly East African DNA test results.

From what I have seen (see this page) the new “Eastern Africa” category on Ancestry is much less predictive for actual East Africans. While interpretation for Afro-Diasporans is often tricky. When it comes to the new “Northern Africa” region on Ancestry the record is mixed. With interpretation again being tricky for Afro-descendants. More clarity may be obtained however when you critically assess your North and/or East African DNA matches, if you happen to have them. Taking into account shared segment size and the possibility of population matches and false positives, so that only genuine IBD matches are left over. Scroll down to sections 3 & 4 of this page for how I performed such a task for 50 Cape Verdeans and their 180 North African & 9 East African matches. 

Over all I would say that my African survey findings are pretty much reinforcing the main message I have been trying to get across from day 1: the labeling of ancestral categories in DNA testing is often not be taken too literally. However this does not mean you cannot derive a great deal of informational value from your socalled ethnicity estimates! Proper interpretation is a precondition. And it has been my experience that being aware of the DNA results of native Africans certainly helps in this regard. Even more so when also taking into account your African DNA matches, relevant historical context, (advanced) genetic genealogy and other means of follow-up research.

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Compil NEA

 

Final summary: Central & Southern African AncestryDNA results 2013-2018

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Without wanting to rehash things this blog post and following ones will provide a quick recap of my final AncestryDNA survey findings for continental Africans. These results were obtained during 2013-2018 but I had not fully processed all the data up till now. Starting with my Central & Southern African section. Which I first published on 17 February 2017 when I had only 32 Central & Southern African AncestryDNA results available for my analysis (see this overview). As my survey has been ongoing I have managed to collect a sample group which is now three times greater. Consisting of no less than 96 AncestryDNA results of Central & Southern African persons! Follow the link below for detailed analysis & new screenshots:

Table 1 (click to enlarge)

stats (n=92)

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I discontinued this survey after Ancestry’s update in September 2018. Because in my opinion Ancestry’s new version of their ethnicity estimates regrettably has been a downgrade in regards to their African breakdown, overall speaking (see also this blogseries). Which is why I think these “old” results may still be useful and are not obsolete yet. I originally singled out two main implications for Afro-Diasporans or rather propositions which I will briefly revisit in this blog post. Also in order to tie up some loose ends.

  1. Congolese & Angolan ancestry more likely than Cameroonian ancestry?
  2. Southwestern Bantu ancestry much more likely than Southeastern Bantu ancestry?

Then again my intention is not only to look backwards but also forwards! In particular I believe that this dataset may provide a helpful baseline to compare with 23andme’s newly updated African breakdown (see this overview). As well as functioning as a benchmark for Ancestry’s upcoming update, which hopefully this time will lead to improvement!

Over all I would say that my African survey findings are pretty much reinforcing the main message I have been trying to get across from day 1: the labeling of ancestral categories in DNA testing is often not be taken too literally. However this does not mean you cannot derive a great deal of informational value from your socalled ethnicity estimates! Proper interpretation is a precondition. And it has been my experience that being aware of the DNA results of native Africans certainly helps in this regard. Even more so when also taking into account your African DNA matches, relevant historical context, (advanced) genetic genealogy and other means of follow-up research.

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compil CSA3

A selection of some of the new results I have added into my survey. Extending the country range. And finally now also able to showcase Angolan breakdowns. Take notice that one of them has “Cameroon/Congo” as primary region while the other shows so-called “Southeastern Bantu” in first place!

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DNA matches reported for 50 Cape Verdeans on AncestryDNA (part 1)

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In this two-part blogseries I will analyze the DNA matches being reported by AncestryDNA for 50 of my Cape Verdean survey participants. A follow-up to my previous blog post about 100 Cape Verdean AncestryDNA results (see this link). Because I was kindly given access to their profiles I was able to use my scanning and filtering method of DNA matches in Excel (see this link). Aside from matches with mainland Africans I am also including matches with people of (presumably) fully Portuguese, Jewish, West Asian and South Asian descent.1 Below a statistical overview of my main findings. Going by group averages. For the individual results which do display greater variation follow this link:

Table 1 (click to enlarge)

DNA matches for 50 CV's

This table is based on group averages. Except for the columns mentioning the frequency of close and zero matches. So for example among my 50 survey participants only one single person received a close African match (>20cM). While two persons did not receive any African matches at all (excl. North Africa). But on average 5 African matches were reported of whom 4 were connected to the Upper Guinea area. (Senegal-Sierra Leone). The average admixture amounts are based on the recently updated Ethnicity Estimates on AncestryDNA. This update strongly reduced the trace regions. Especially for North African & West Asian DNA. For a previous version of this table see this link.

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Table 2 (click to enlarge)

African matches

The background column is mostly based on informed speculation (plausible surnames/regional admixture) but at times also confirmed by public family trees. The proportion of Upper Guinean related matches is 88% of all African matches (south of the Sahara). That proportion being equal to 227/257. Excluding North African matches from the total. The high number of Fula matches is quite striking. But this could very well reflect a greater popularity of DNA testing among Fula people when compared with people from for example Guiné Bissau who are greatly underrepresented in Ancestry’s customer database.

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This project was merely intended as an exploratory exercise. Of course my research findings have limitations in several regards. And therefore they should be interpreted carefully in order not to jump to premature or even misleading conclusions. Still I do believe they can reveal relevant tendencies in DNA matching for Cape Verdeans in general. These outcomes may also provide valuable insight into the various ancestral components found within Cape Verdean DNA. In particular when aiming for complementarity by also taking in to account admixture analysis, genealogy and relevant historical context.

Below an overview of the topics I will cover in this blog post:

  1. Considerations when dealing with DNA matches
  2. Upper Guinean matches: as expected African matches (south of Sahara) were overwhelmingly from Upper Guinea (Senegal-Sierra Leone): 88% of the total. In line with the 92% Upper Guinean admixture proportion  (“Senegal” + “Mali” / total African) I found for my survey group.
  3. North African matches: fairly consistent despite minimal shared DNA
  4. Other African matches: unexpected & uncommon. Higher odds of false positives but in some cases to be corroborated by additional clues, such as AncestryDNA’s ethnicity estimates?
  5. Methodology: how I filtered the African DNA matches as well as the decision rules I applied when determining a plausible background for each DNA match.

Part 2 of this blogseries will have the following topics:

  1. Portuguese matches: omnipresent and clearly most numerous as well as often hinting at relatively recent ancestral ties (1800’s-1900’s).
  2. Jewish matches: Sephardi matches more likely to be truly genealogical than Ashkenazi matches?
  3. West Asian matches: quite rare, possibly indicating that West Asian admixture among Cape Verdeans is generally indicative of actual North African or Sephardi lineage.
  4.  South Asian matches: also rare, but on a hit and miss basis still sometimes already seemingly validating trace amounts of South Asian admixture.
  5. Inter-island matching patterns: illustrated by the distribution of the shared DNA segments between myself and my 100 Cape Verdean survey participants.
  6. Methodology: how I filtered the non-African DNA matches as well as the decision rules I applied when determining a plausible background for each DNA match.

Dedicated to all my Cape Verdean primos and primas participating in this survey.2 And special dedication to my newly born nephew Max!

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100 Cape Verdean AncestryDNA results

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In October 2015 I published my first preliminary survey findings based on 23 Cape Verdean AncestryDNA results (see this link). Right now, almost three years later, I have managed to collect a sample group which is four times greater. Consisting of no less than 100 AncestryDNA results of fully Cape Verdean-descended persons! Even though this quadrupled sample size is obviously still limited it will most likely provide a greater insight in the various ways how “Caboverdeanidade” can be described. Genetically speaking that is. And obviously when applying the regional AncestryDNA format, with all its enhanced features as well as its inherent shortcomings  😉

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capeverdednalogo2

Click on this banner to reach Cape Verde DNA, Inc: the biggest online community of Cape Verdean Genealogy & DNA enthusiasts! On Augustus 4 & 5 a pioneering Cape Verde DNA and Genealogy Conference will be held! See this link for more details.

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In this blog post I will discuss the main differences with my previous findings from 2015, which were focused on the African breakdown solely. And in addition I will also present some new statistics and background information on the European and other non-African origins of Cape Verdeans as reported by AncestryDNA. Below an overview of all the topics I will cover:

  1. Background details of my 100 Cape Verdean survey participants
  2. To be Cape Verdean is to be mixed?
  3. Upper Guinean roots = “Senegal” + “Mali”
  4. Beyond Upper Guinea: valid outcomes or misreading by AncestryDNA?
  5. European breakdown reflecting mostly Portuguese ancestry?
  6. “Africa North”, “Middle East”, “European Jewish” and other minor regional scores
  7. Upcoming update of AncestryDNA’s Ethnicity Estimates

Follow these links for my complete survey data & research methodology:

Table 1 (click to enlarge)

cvstats

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Chart 1 (click to enlarge)

Primary regions

This frequency of regions being ranked #1 (regions with the highest amount in either the African or European breakdown) is perhaps the best indicator of the main ancestral components for my Cape Verdean survey group. However only in an extra pronounced degree. For more nuance see the group averages in the next sections.

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Screenshots of individual results (rightclick and open in new tab to enlarge; island origins shown below)

This slideshow requires JavaScript.

More charts and analysis when you continue reading!

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Update: Afro-Diasporan AncestryDNA Survey (part 2)

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In May 2016 I published the first summary of my Afro-Diasporan survey findings based on 707 results for 7 nationalities (see this blog page). My survey has been ongoing ever since. Right now an update of AncestryDNA 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 😉 See this link for the first part of my findings which is focused solely on the African breakdown:

In order to provide a broader perspective on the complete DNA make-up of Afro-Diasporans I have this time also analyzed the non-African regional scores on AncestryDNA. Enabling a continental breakdown for my 8 sample groups. Mainly based on 860 results for people from 8 nationalities1. Although the total number of results and nationalities in my survey is even greater.

Generally speaking also the non-African group averages seem to be reasonably in line with historical plausibility. Amerindian, Asian and Pacific trace-amounts are not being left out. These scores are often labeled as low confidence regions and dismissed as just “noise”. Rightfully so in some cases. But given correct interpretation and proper follow-up research at times these scores can still potentially lead you to distinctive ancestors. Furthermore my survey results are now also allowing for a more detailed discussion of the European breakdown as being reported for Afro-Diasporans.

I would like to underline right from the start that my findings are not intended to represent any fictional national averages! The group averages I have calculated for my sample groups are neither absolute or conclusive but rather to be seen as indicative. Obviously several shortcomings may apply. One main aspect to take to heart is that there will always be individual variation around the mean. Given correct interpretation I do believe these group averages suggest insightful tendencies though for each of my 8 sample groups. They also mostly comply with the findings of admixture studies published in peer reviewed journals, or at least the ones I am aware of.2

Chart 1 (click to enlarge)

Continental breakdown

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Update: Afro-Diasporan AncestryDNA Survey (part 1)

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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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“Benin/Togo” also describes DNA from Ghana & Nigeria

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I have created a new page featuring the AncestryDNA results for West Africans from the following countries: Liberia, Ivory Coast, Burkina Faso, Ghana, Togo & Benin. I will create a new section for the remaining part of West Africa (Upper Guinea) shortly. The number of results I have collected so far might be minimal but already my survey findings turn out to be quite insightful. I also provide some statistical data, analysis and relevant context. Follow this link to view the page:

In addition I also discuss the implications these findings might have for Afro-Diasporans in an attempt to improve proper interpretation of their West African regional scores, in particular for “Ivory Coast/Ghana” and “Benin/Togo”. One of these implications I will also discuss in greater detail in this blog post:

“Benin/Togo” is also predictive of Ghanaian & Nigerian DNA

The so-called “Benin/Togo” region seems to be quite predictive of Beninese origins (based on two results). However in addition ancestry from eastern Ghana and southern Nigeria might also be described by this region. You will need to perform your own follow-up research in order to find out more specifics.

Map 1 (click to enlarge)

Benin Togo

Source: ancestry.com

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Chart 1 (click to enlarge) 

Stats (GH=22)

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“Ivory Coast/Ghana” also describes Liberian DNA

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I have created a new page featuring the AncestryDNA results for West Africans from the following countries: Liberia, Ivory Coast, Burkina Faso, Ghana, Togo & Benin. I will create a new section for the remaining part of West Africa (Upper Guinea) shortly. The number of results I have collected so far might be minimal but already my survey findings turn out to be quite insightful. I also provide some statistical data, analysis and relevant context. Follow this link to view the page:

In addition I also discuss the implications these findings might have for Afro-Diasporans in an attempt to improve proper interpretation of their West African regional scores, in particular for “Ivory Coast/Ghana” and “Benin/Togo”. One of these implications I will also discuss in greater detail in this blog post:

“Ivory Coast/Ghana” is also predictive of Liberian & Sierra Leonean DNA

The socalled “Ivory Coast/Ghana” region is indeed quite predictive of both Ghanaian and Ivorian origins. However in addition ancestry from Liberia and to a lesser degree (southern) Sierra Leone might also be described by this region. You will need to perform your own follow-up research in order to find out more specifics.

Map 1 (click to enlarge)

IvcGhana region

Source: ancestry.com. (text in red added by myself)

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Chart 1 (click to enlarge) 

Stats (GH=22)

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“South-Central Hunter-Gatherers” suggestive of remnant West African Pygmy DNA?

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I have created a new page featuring the AncestryDNA results for West Africans from the following countries: Liberia, Ivory Coast, Burkina Faso, Ghana, Togo & Benin. I will create a new section for the remaining part of West Africa (Upper Guinea) shortly. The number of results I have collected so far might be minimal but already my survey findings turn out to be quite insightful. I also provide some statistical data, analysis and relevant context. Follow this link to view the page:

In addition I also discuss the implications these findings might have for Afro-Diasporans in an attempt to improve proper interpretation of their West African regional scores, in particular for “Ivory Coast/Ghana” and “Benin/Togo” as well as “South-Central Hunter-Gatherers”. One of these implications I will also discuss in greater detail in this blog post:

 “SC Hunter-Gathers” can also be predictive of West African ancestors

  • In particular Liberian, Ivorian and Sierra Leonean ancestors might have passed on socalled “Africa South-Central Hunter-Gatherers” DNA markers, which are also present in their own genome. The “Africa South-Central” labeling by AncestryDNA is therefore not to be taken too literally. Despite usually appearing as “low confidence” trace region this still represents a very distinctive type of DNA.

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PS (4x)a

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AncestryDNA results from Asia, the Pacific & Native Americans

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As the name already implies this blog is dedicated to Tracing African Roots. However many if not most Afro-descendants actually also have additional non-African ancestry. And for some people this part of their DNA might also be interesting to explore further. I have therefore started a new survey featuring the AncestryDNA results of persons from all over Asia, the Pacific as well as Native Americans. In order to improve correct interpretation of AncestryDNA’s regions by comparing results with persons from verified backgrounds. At the very end of this blog post i will attempt to outline some of the most important implications for Afro-Diasporans who have received any Asian, Native American or Pacific regions in their AncestryDNA breakdown.

I am currently creating new blog sections to feature screenshots of these results. Statistical data, background information and relevant context will also be provided. Follow these links for more details:

***Chart 1 (click to enlarge)

STATS (Iran, n=15)

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