Category Archives: DNA Studies

Ancestry’s 2019 Update: Back on Track Again?

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Backontrack

Map showing all the regions available on Ancestry after its 2019 update. For Trans Atlantic Afro-descendants the most impactful changes seem to be that: “Nigeria” has been brought back to life again! But “Ghana” has been derailed. “Mali” is no longer overpowering “Senegal”, but it does include both Sierra Leone and Liberia now! See this link for a complete list of regions and genetic communities. Photo credits for top picture showing a train passing by a railway station in Ghana.

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Starting in October 2019 Ancestry has been rolling out a new update of their Ethnicity Estimates. As I have said before your DNA results are only as good as the next update. So it is best not to get too attached to them 😉 Given scientific advancements and a greater number of relevant reference samples one always hopes that a greater degree of accuracy may be obtained. But naturally no guarantees are given that this will indeed be the case. After all Ancestry’s update in 2018 arguably was a downgrade rather than providing any meaningful improvement! At least when it comes to the African breakdown. In regards to the European, Asian and Amerindian breakdown Ancestry seems to have made steady progress on most fronts. Continued also with this 2019 update.

From my experience the best indication of predictive accuracy is obtained by looking at how Africans themselves are being described when tested by Ancestry. Which is why I have performed a comprehensive survey among 136 African Ancestry testers from all over the continent to establish a more solid basis for judgement. In addition I have also looked into a representative array of 55 updated results from across the Afro-Diaspora. These findings will be described in greater detail further below. The outcomes are mostly positive for Africans themselves but more ambivalent for Afro-descendants. Probably because Ancestry’s algorithm is less adequate when describing the mixed and therefore more complex African lineage of the Afro-Diaspora. My overall verdict about this 2019 update: a step in the right direction but no substantial improvements for the most part. At least not when compared with the original African breakdown from the 2013-2018 version.

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Table 1 (click to enlarge)

Stats Afro

Based on the updated results for 121 African AncestryDNA testers from 30 countries, across the continent. Take notice that the predictive accuracy in most cases is quite solid. Although in a few cases it is still clearly in need of improvement. This goes especially for “Ghana” and “Eastern Bantu”. Follow this link for my spreadsheet containing all the individual results.

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Due to wild fluctuations in just two years many people might experience update fatigue. Some people will even be tempted to bash their DNA test results and admixture analysis in particular. But an overtly dismissive stance will be self-defeating and deprive you of informational value yet to be gained! As I have always argued that regional admixture DOES matter and Ancestry’s Ethnicity Estimates are of course NOT randomly determined.1 Ancestry’s predictions may not be 100% accurate but still in most cases they are reasonably well-aligned with the known backgrounds of my African survey participants. As can be verified from the overview above.

For those perplexed by all the changes do at least make an attempt to inform your self properly. Given how wrong Ancestry got it in 2018 (see this blog series) it is only natural that some grave flaws had to be rectified. Regrettably it seems in some aspects an over-correction did take place. Still depending on your background this update certainly also can be beneficial. Furthermore when considering your African breakdown in a macro-regional framework the changes have actually not been that drastic. And many things more or less remained consistent as I will discuss in section 3 of this blog post.

It has always been my belief that regional estimates require correct interpretation. And each updated version as well as each separate DNA testing company should therefore be judged on its own terms. Then again these admixture results can only take you that far. My advise is to also look into your African DNA matches, as well as historical plausibility and just plain genetic genealogy for greater combined insight. See also these links:

For those seeking deeper understanding of Ancestry’s 2019 update this blog post will attempt to take things further by having a closer look at:

  1. African breakdown for Africans before and after the 2019 update
  2. Ancestry’s Reference Panel & Algorithm
  3. African breakdown for Afro-descendants before and after the 2019 update
  4. Getting back on track again
  5. Screenshots of African updated results
  6. Poll on whether this update has been an improvement or not, please vote!

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100 Jamaican AncestryDNA Results (2013-2018)

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On 9 October 2015 I published my first preliminary findings based on 19 Jamaican AncestryDNA results (see this link). Right now, four years later, I have managed to collect a sample group which is five times greater! Consisting of no less than 100 AncestryDNA results of Jamaican-born or fully Jamaican descended persons.1 Although still limited this data-set already provides a rather robust basis. Allowing for a finer detailed analysis of Jamaican genetics. In the first place with regards to the African regional roots of Jamaicans. But in addition I will also cover the Amerindian, Asian and European admixture scores being reported for Jamaicans on Ancestry. As well as variation in African admixture in general. With a special focus on substructure.

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JAMDNA

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These results were obtained during 2013-2018 but I had not fully processed all the data up till now. Although actually in 2018 I already blogged about this survey group (n=100) in my comparison of various parts of the Afro-Diaspora:

Please keep in mind that AncestryDNA’s ethnicity estimates have been updated several times now! In this blog post I am dealing exclusively with AncestryDNA version 2 which was current between September 2013 and September 2018. All matters being discussed are therefore not pertaining to recently updated results (2018/2019) (unless mentioned so specifically). In my opinion especially version 3 (Sept 2018 – Oct. 2019) has been a downgrade rather than providing any meaningful improvement when wanting to learn more about one’s African origins (see this blogseries). The update which is currently rolled out will be reviewed at a later time.

I will mainly revisit and expand on previous findings. Using new statistics and background information. Furthermore I will present my preliminary 23andme survey findings for 28 Jamaicans. This blog post is also intended to be a prelude for my current research into the African DNA matches being reported for Jamaicans. Which will be featured in a follow-up post to this one. Below an overview of all the topics I will cover:

  1. African regional breakdown in line with expectations?
  2. Variation & substructure in African admixture levels
  3. European breakdown reflecting mostly British ancestry
  4. Asian admixture: more or less widespread than imagined?
  5. Traces of Amerindian admixture is proof of enduring Taino legacy?
  6. Comparison with 23andme results being reported for Jamaicans
  7. Current update of AncestryDNA’s Ethnicity Estimates 
  8. Screenshots of individual results & Youtube videos

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

Table 1 (click to enlarge)

Macro

This table features an additional breakdown of my own making into 3 greater macro-regions: “Upper Guinea”, “Lower Guinea” and “Central Africa” (also includes Southeast Africa). I find this distinction useful because it allows certain regional patterns to show up more clearly. In particular it seems apparent that the bulk of Jamaica’s African roots are from the area in between Ghana and Nigeria (=Lower Guinea).

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Table 2 (click to enlarge)

Cont. breakdown JAM

The continental breakdown is often considered to be the most reliable within admixture analysis. Aside from reviewing the group averages it is recommendable to look into other statistical measures as well. As many people tend to have misconceptions on how “typical” their personal results might be. Compare also with my 23andme surveyfindings (n=28), see this table.

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Fula, Wolof or Temne? Upper Guinean AncestryDNA results 2013-2018

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This blog post will feature a summary of my Upper Guinean AncestryDNA survey findings. A fitting conclusion of my African AncestryDNA research as I am myself of Cape Verdean descent. And therefore this particular section was of paramount significance to understand my own African Roots! These results were obtained during 2013-2018 but I had not fully processed all the data up till now. Relatively few African customers of Ancestry are hailing from this particular area. Which is why it was difficult to gather a sufficient sample size. But eventually I did succeed. Also through the valuable help of several friends!1 Follow the link below for detailed analysis & screenshots:

Table 1 (click to enlarge)

Stats, SEN, n=34

“Senegal” is primary for most countries throughout the wider Upper Guinea area. Usually with “Mali” as secondary region. This goes even for the northern part of Sierra Leone. But this country shows greater variation. With “Ivory Coast/Ghana” also being a prominent component overall. An almost equal “Mali” group average (38-39%) was obtained for 6 samples from Mali when compared with 3 Gur/Senoufo speaking samples from Burkina Faso, Ivory Coast & Ghana.

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Table 2 (click to enlarge)

Stats Fula

A clearly detectable Upper Guinean component is mirrored among the Fula from across Upper Guinea and the Hausa-Fulani. Indicating their shared Upper Guinean origins by way of eastwards moving Fula migrations. However due to their partial Nigerian Hausa lineage the Hausa-Fulani results can still be quite easily distinguished through their primary “Nigeria” scores.

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My final survey group now consists of 122 AncestryDNA results from Senegal, Gambia, Guiné Bissau, Guinea, Sierra Leone, Mali and Mauritania. Although still limited this data-set already provides a rather robust basis. All the more given that my combined survey group (n=122) contains a number of people which is almost three times greater than Ancestry’s Upper Guinean Reference Panel at that time (n=44; 28 samples being used for “Senegal” + 16 samples for “Mali”).

And also crucially I have managed to gather plausible ethnic details for many of my survey participants. Enabling me to compile a separate Fula survey group (n=46) which is quite extra-ordinary as it includes Fula people from a wide range of countries (see Table 2). While usually in published studies only Fula samples from one particular area are being covered (often from the central/eastern Sahel and not from Upper Guinea).

To a lesser extent I also uncovered more specific ethnic backgrounds among my Sierra Leonean and Senegambian survey groups. Allowing for a finer detailed ethnic analysis of Upper Guinean genetics. Which is why I think these “old” results may still be useful and are not obsolete yet. Even when I did discontinue 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).

Five main implications for Afro-Diasporans can be singled out. These are discussed in greater detail on the main page. In this blog post I will mostly elaborate on the question if it is possible to distinguish Upper Guinean DNA. Furthermore I will briefly touch upon 23andme’s new “Senegambian & Guinean” category and also how Ancestry might improve things in the near future. Especially in light of their upcoming update.

  1. “Senegal” + “Mali” combined is a solid indication of lineage across Upper Guinea (Senegambia, Guinea Bissau/Conakry, Sierra Leone, western Mali).
  2. “Mali” can also be predictive of DNA found in Burkina Faso, northern parts of Ivory Coast & Ghana.
  3. “Ivory Coast/Ghana” can also be predictive of Sierra Leonean DNA
  4. “Africa North” might also be inherited by way of Fula ancestors
  5. “South-Central Hunter-Gathers” can also be predictive of West African ancestors

In summary: Regional admixture DOES matter! Judge each case on its own merits. Combine insights from different fields to achieve complementarity!

Figure 1 (click to enlarge)

COMPILUG

The two first results illustrate how AncestryDNA’s 2013-2018 version was able to clearly distinguish between Fula & Wolof lineage (for Africans themselves!). The additional “Africa North” and “Middle East” scores making the difference. To a lesser degree also within Sierra Leone some ethnic differentiation (going by group averages) could be observed. Obviously there was greater individual variation though. And in no way was either “Senegal” or “Mali” an exclusive marker for any given ethnic group! For Afro-Diasporans follow-up research is therefore required (DNA matches, historical plausibility, genetic genealogy etc.).

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Akan or Ewe? West African AncestryDNA results 2013-2018

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Without wanting to rehash things this blog post and one more upcoming 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. Arriving now at the first part of my West African section. Which contains results from Liberia, Ivory Coast, Burkina Faso, Ghana & Benin. One striking research outcome was the clear distinction between Akan & Ewe results.

I first published my preliminary West African survey findings on 24 February 2018 when I had only 41 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 doubled in size. Consisting of no less than 82 AncestryDNA results from Liberia, Ivory Coast, Burkina Faso, Ghana and Benin! Follow the link below for detailed analysis & new screenshots:

Table 1 (click to enlarge)

Stats (n=82)

Notice the striking difference in group averages for “Ivory Coast/Ghana” and “Benin/Togo” for my Akan and Ewe survey participants. Although actually there was also much underlying individual variation (see this more detailed overview).

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Aside from my Nigerian survey group (n=87) the sample size of my Ghanaian survey group (n=42) was the biggest within my entire African survey. Although still limited this already provides a rather robust basis. And also crucially I have managed to gather plausible ethnic details for almost all of my Ghanaian survey participants. Allowing for a finer detailed ethnic analysis of Ghanaian genetics. Which is why I think these “old” results may still be useful and are not obsolete yet. Even when I did discontinue 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).

I originally singled out three main implications for Afro-Diasporans. All of which can be maintained and have been discussed already in previous blogs. In this blog post I will revisit the question if it is possible to distinguish Akan from Ewe lineage. Furthermore I will briefly touch upon 23andme’s new “Ghanaian, Liberian and Sierra Leonean” category and also how Ancestry might improve things in the near future. Especially in light of their upcoming update.

  1. “Benin/Togo” also describes DNA from Ghana (see this blog post as well)
  2. “Ivory Coast/Ghana” also describes Liberian DNA
  3. “South-Central Hunter-Gatherers” suggestive of remnant West African Pygmy DNA?
  4. Is it possible to determine the most likely ethnic source(s) of your Ghanaian lineage?

Figure 1 (click to enlarge)

Compil GH

The two first results are most illustrative of how AncestryDNA’s 2013-2018 version was able to  clearly distinguish between Akan & Ewe lineage (for Ghanaians themselves!). Obviously there was greater individual variation though. And in no way was either “Ivory Coast/Ghana” or “Benin/Togo” an exclusive marker for any given ethnic group! Ghanaians will usually know of course (even when going back several generations they might also be more multi-ethnic than they are aware of). However for Afro-Diasporans follow-up research is required (DNA matches, historical plausibility, genetic genealogy etc.).

 

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Igbo, Yoruba or Hausa-Fulani? Nigerian 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. Moving on now to Nigeria, with a special focus on how to distinguish Igbo, Yoruba and Hausa-Fulani lineage.

I first published my preliminary Nigerian survey findings on 22 September 2016 when I had only 15 Nigerian 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 five times greater. Consisting of no less than 87 AncestryDNA results of Nigerian persons! Follow the link below for detailed analysis & new screenshots:

Table 1 (click to enlarge)

naija comparison

For all three listed ethnic groups “Nigeria” is the primary regional component. However more differentiation is detectable when zooming into secondary regions. In particular “Senegal” for the Hausa-Fulani clearly stands out when compared with the rest. Less clear-cut distinction between Igbo & Yoruba. However when taking into account relative proportional shares for “Benin/Togo” and “Cameroon/Congo” it is still already detectable.

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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. In particular Ancestry’s update in 2018 has been disastrous for obtaining reasonable Nigerian DNA results. Generally speaking former “Nigeria” scores have sharply decreased and were replaced by inflated “Benin/Togo” and “Cameroon, Congo, Southern Bantu” scores. Just as a reminder this blog post is NOT dealing with those updated and usually rather misleading results! Instead read this blogseries.

My Nigerian AncestryDNA survey is actually the most extensive and oldest part of my African survey (2013-2018). Such results initially being very difficult to come by. However currently my sample size (n=87) is rather robust. Higher even than Ancestry’s own Nigerian sample size (n=67) during this period! And also crucially I have managed to gather plausible ethnic details for almost all of my Nigerian survey participants. Allowing for a finer detailed ethnic analysis of Nigerian genetics. Which is why I think these “old” results may still be useful and are not obsolete yet. Even when I did already establish in 2016 that “Nigeria” does not not cover the full extent of one’s Nigerian lineage.

I originally singled out three main implications/propositions for Afro-Diasporans. The first two ones have been discussed already in previous blogs. However not so the last one which I will revisit in this blog post. Furthermore I will briefly touch upon 23andme’s new “Nigerian” category and also how Ancestry might improve things in the near future.

  1. “Benin/Togo” also describes DNA from Nigeria (see this blog post as well)
  2. “Cameroon/Congo” can also be partially indicative of southeastern Nigerian lineage (usually to a minor degree though, see this blog post)
  3. Is it possible to determine the most likely ethnic source(s) of your Nigerian lineage?

Figure 2 (click to enlarge)

Compil NG 3x

All three results show a predominant “Nigeria” amount. Indicative of a high degree of shared origins for Nigerians, regardless of ethnic background. Then again there is a major distinction between Hausa-Fulani and southern Nigerian results because of in particular the additional “Senegal” score and absence of “Benin/Togo” & “Cameroon/Congo”. Overlap between Yoruba and Igbo results is much greater but still going by proportional shares for in particular “Cameroon/Congo” still some minor differentiation can be detected.

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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)

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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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