Are African Americans really mostly “Nigerian”?

Last year 23andme’s research team published a major landmark study titled “Genetic Consequences of the Transatlantic Slave Trade in the Americas“. Arguably the largest DNA study to examine African ancestry in the Americas! Covering a wide span of the Afro-Diaspora, incl. also several thousands of African Americans. Highly interesting therefore. The research approach of this study consists of combining genetic data obtained from 23andme customers with Trans-Atlantic Slave Trade patterns. Which is practically the same approach I have been using ever since I started my AncestryDNA survey in 2013. This study by 23andme is even including Cape Verdean samples as a control group! Which is something I have done as well in all my research sofar.1 Since I have recently finished my survey findings based on 23andme results (2018/2019 version) it should be useful to compare notes.

23andme’s 2020 study

My own survey findings based on 23andme and AncestryDNA results

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Table 1 (click to enlarge)

This overview is showing the scaled African breakdown for the combined USA sample group (n=5785) featured in Micheletti et al. (2020). As well as for my own African American survey group (n=200). Despite smaller sample size actually very similar outcomes. Providing mutual corroboration. As can be seen “Nigerian” was clearly the most significant region. Going by group averages around 35%. Usually “Nigerian” is appearing as primary African category (162/200=81% in my survey). But even so “Nigerian” is still far from being predominant (>50%). Especially “Ghanaian, Liberian & Sierra Leonean” is also showing up as a substantial component. Furthermore regional scores indicative of Senegambian and Central African DNA are still considerable and nearly at 10%, on average. Making for an overall varied and rather balanced African breakdown. Do notice as well that around 20% of the African breakdown is falling in one of the “Broadly” categories!

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In this blogpost I will compare my own research findings (based on regional admixture) with 23andme’s study from 2020. In fact much of the data contained in 23andme’s study (based on the 2018 version of Ancestry Composition) is consistent with my own. As demonstrated above in Table 1. Which features the African breakdown for African Americans on 23andme (scaled to 100%).2 Despite smaller sample size on my part actually very similar outcomes. Providing mutual corroboration. The study’s main findings of lower Senegambian and higher Nigerian ancestry than expected for African Americans are in line with what I had already established in my 2015 survey. Based on AncestryDNA test results for 350 African Americans. As well as more recently in my 23andme survey. See also:

Within the remaining part of this blog post I will discuss the following:

  1. Why do so many African Americans have Nigerian ancestry?
    • Ancestral implications of “Nigerian” go beyond modern-day borders
    • Domestic Slave Trade from mostly Virginia spreading Bight of Biafra lineage
    • Lower Senegambian than expected because of less reproduction?
    • Substructure according to state origins
  2. African breakdown for other parts of the Afro-Diaspora 
    • Mostly in agreement with historical expectations
    • Overlap & differences with my own survey findings
    • Regional diversity and substructure
    • Confirmation of Upper Guinean Founding Effect?
  3. Discordances & limitations of 23andme’s study
    • Afro-descended samples taken from migrants underrepresent wider variation in countries of origin
    • Central African IBD disproportionately high when contrasted with regional admixture from Central Africa 
    • Sex-biased admixture: multiple & context-dependent historical narratives! 
  4. Exciting future prospects:  personalized 23andme results featuring African IBD specified according to ethnic groups Continue reading

Gullah Genetics

I have published another new page within the 23andme section of my blog. It features my survey findings based on 100 23andme results as well as 68 AncestryDNA results for African Americans with deep roots from South Carolina. Incl. several Gullah persons! Most of my findings are in agreement with previous published studies on African American genetics. In line with expectations Rice Coast related DNA seems to be more elevated indeed among South Carolinians.1 As indicated firstmost by a high frequency of primary “Ghanaian, Liberian & Sierra Leonean” scores on 23andme. As well as prominent “Mali” scores on Ancestry. But in fact also Central African lineage and strictly Senegambian2ancestry appear to be more pronounced in South Carolina than elsewhere in the USA. To be sure Nigerian (related) ancestry is very common in South Carolina too but intriguingly it seems to be relatively subdued among Gullah persons.

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Table 1 (click to enlarge)

This overview is exploring regional substructure between various parts of South Carolina. Obviously only preliminary due to minimal sample size. However already a very insightful constrast between coastal and inland areas is surfacing. The Lowcountry and Pee Dee clearly having relatively elevated group averages for “Senegambian & Guinean” and especially “Ghanaian, Liberian and Sierra Leonean”. While “Nigerian” scores are much more prominent in Upstate and Midlands. Intriguingly the substantial Central African level showing up in coastal areas is also maintained into Midlands.

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My analysis is also zooming into coastal areas and contrasting with inland areas within South Carolina. And this kind of granularity might be a first when compared with other research projects (along with the inclusion of Southeast Asian admixture statistics). Atleast as far as I know and also when dealing with regional admixture within Africa as well (otherwise see Parra et al. (2001) for a truly pioneering study). Such a comparison is particularly insightful when wanting to grasp the localized formation of the Gullah people in the Lowcountry and adjacent Pee Dee area! In order to avoid any assumptions being made on my part I will not use Gullah as a synonym for people from the Lowcountry and/or Pee Dee.3 Although of course this is the main area where they are located. Follow the link below for fully detailed analysis, references and screenshots (incl. also AncestryDNA results):

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Genetic Landscape of Gullah African Americans (Zimmerman et al., 2020)

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“Relative to southeastern non-Gullah African Americans, the Gullah exhibit higher mean African ancestry, lower European admixture, a similarly small Native American contribution” […]

“Despite a slightly higher relatedness to Sierra Leone, our data demonstrate that the Gullah are genetically related to many West African populations.” 

“This study confirms that subtle differences in African American population structure exist at finer regional levels. Such observations can help to […] guide the interpretation of genetic data used by African Americans seeking to explore ancestral identities.” (Zimmerman et al., 2020)

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In this blogpost I will compare my own research findings with a very interesting recent study on Gullah genetics. This paper, linked above, is currently still in preprint. But it is consistent with several of my own research outcomes. Especially in regards to the quotes above. Impressively the study is based on the autosomal DNA results of 883 unrelated Gullah African Americans! A much larger sample size than I was able to use therefore.

However due to differences in methodology regrettably its potential for breakthrough insights is not fully realized. Resulting in less regionally detailed outcomes than I was able to obtain with my surveys based on 23andme and Ancestry results. To their credit the authors of the study largely succeed in sketching an appropriate historical framework for properly contextualizing their research outcomes. But at times essential details are still lacking while some of the information given appears to be outdated or not well referenced. Within the remaining part of this current blog post I will discuss the following:

  1. Summary of my own survey findings based on 23andme and AncestryDNA results
  2. Review of Genetic Landscape of Gullah African Americans (Zimmerman et al.; 2020)
  3. African DNA matching patterns, beneficial for creating your own narrative about your personal African roots!
  4. Screenshots of 23andme & Ancestry results for African Americans from South Carolina

Continue reading

200 African American 23andme results

I have just published a new page within the 23andme section of my blog. It features my survey findings for 200 African American 23andme results. Various themes/topics are discussed. Especially delving deeper into the African breakdown but also highlighting a remarkably widespread Madagascar Connection for my African American survey group! Follow the link below for fully detailed analysis, references and screenshots:

Of course my 23andme survey may have several limitations. The group averages I have calculated for my survey-(sub)groups are neither absolute or conclusive but rather to be seen as indicative. One main aspect to take to heart is that there will always be individual variation around the mean! Still the sample size of n=200 should be sufficiently robust to pick up on the main tendencies. I have made an extra effort to do justice to the entire African American spectrum across the country. Of course all done on a best-effort basis.

Continental breakdown

Table 1 (click to enlarge) 

Generally speaking most African Americans are clearly of predominant African descent, combined with minor other ancestral components. Almost all of this additional ancestry will usually be European in fact. Often to a minor but still substantial degree. Aside from much more diluted but still distinctive amounts of especially Native American and perhaps more surprisingly also Southeast Asian admixture! See this screenshot for an overview of my previous Ancestry survey findings (n=350). And also this one featuring the complete continental breakdown (n=200). The overall group averages being nearly identical!

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At the same time I have also focused on gathering atleast a minimum number of 20 survey participants each for Louisiana, South Carolina and Virginia. These are 3 key states when considering African American genetics & origins.

Table 2 (click to enlarge)

The state origins of my survey participants are not based on a 4 grandparents criterium per se. But often this was indeed confirmed by their profile details on 23andme. Either way insightful variation according to state origins. Take notice especially of the highest subgroup averages which have been highlighted in red. The African admixture ranges (min. – max.) were as follows: Louisiana (51%-94%); South Carolina (75%-99%) ; Virginia (56%-94%). Compare also with my previous survey findings on Ancestry.

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Chart 1 (click to enlarge)

This chart is showing the full extent of African ancestry among my African American survey participants. The most frequent African admixture interval is 80-90%.  Which is the same as it was during my  previous Ancestry survey (n=350, see this chart).

Continue reading

Update of 23andme’s African breakdown

After a long delay of any meaningful improvements 23andme has actually implemented several updates in the last two years. Often beneficial for Tracing African Roots! Starting with the introduction of a new African regional framework in 2018. In 2019 new reference samples were added for especially North Africa. While also the potentially very useful Recent Ancestor Locations feature has been greatly expanded. In this year 23andme has decided to upgrade their customized algorithm. Unlike the 2019 update this upgrade is poised to have a considerable impact on 23andme’s African breakdown. 

Not per se in a positive way though. As it seems that 23andme’s algorithm tends to be “over-smoothing”. That is to say it will tend to homogenize people’s DNA in just a few categories.1 As always one needs to refrain from being overly dismissive in order to also capitalize on any positive aspects. From what I have seen sofar this update does seem to be an improvement for many Afro-descendants, at least on balance. Of course I would need to see more updated results for a more substantiated judgement. For more details read:

Figure 1 (click to enlarge)

General trends of changes after 23andme’s update. According to 23andme (see this link).  The decrease in “unassigned” and most of the “broadly” categories is certainly observable. And especially within the European breakdown this will often be an improvement for Hispanics and African Americans. From what I have seen sofar actually an increase of “Nigerian” is not always happening for African Americans, or only marginally so. Also “Broadly West African” does not seem to change that much. But in particular “Angolan & Congolese” might often show a considerable increase. Often it seems at the expense of “Broadly Sub-Saharan African”.

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Either way it seems that this upgrade is likely to be rolled out to everyone and not just so-called V-5 customers. That is to say regardless of when you tested 23andme is aiming to eventually update your results using their new algorithm. At the latest early next year, 2021. Initially there was some confusion on whether “old” customers of 23andme (genotyped on the v1-v4 chips) would also receive this update. However quite recently 23andme’s customer service made this clarifying statement on 23andme’s forum:

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In October of this year, we completed testing and validating the updated algorithm for the latest genotyping platform (v5) and decided to release this update to v5 customers while continuing to work on testing and validating the updated algorithm for previous genotyping platforms (v1 through v4). These processes are independent: the set of variants tested on the v5 genotyping chip is different from the set tested on prior chips. This means that updates for customers on current and previous chips require independent research, testing, and validation. While we cannot guarantee that the new algorithm will pass quality control checks when applied to earlier genotyping platforms, we hope to provide this update to pre-v5 customers by early next year“. (source, or see also this screenshot for complete statement)

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For the sake of correct interpretation of 23andme’s African breakdown I performed a comprehensive survey among African 23andme testers from all over the continent in 2019. This survey (based on 23andme’s 2018/2019 version) was ongoing up till now. At this point my African 23andme survey includes 314 people from 36 countries! By looking into their group averages you can get a pretty good idea on how well 23andme is able to describe the African origins of people who are already aware of their specific African lineage. Because I have been able to expand my survey I can now comment in greater detail about the predictive accuracy of 23andme’s African breakdown (2018/2019 version). Beyond what I had already established in 2019.2 In the remaining part of this blog post I will discuss the following:

  1. African surveyfindings (2018-2019 version)
    • “Nigerian” also partially describes Ewe lineage from Ghana 
    • “Angolan & Congolese” is not always fully covering Central African DNA 
    • “Sudanese” is also being reported for Sahellian West Africans, incl. Tuareg
  2. Screenshots before & after 2019 update (Africans & Afro-descendants)
  3. Screenshots before & after 2020 update (Africans & Afro-descendants)

Continue reading

Ancestry’s new African Breakdown: merely cosmetic changes?

Only a few weeks ago Ancestry went ahead with their ill-advised deletion of smaller DNA matches (6-8 cM). Resulting in a great loss of customer value. But already the next update is being rolled out. This time once again our Ethnicity Estimates are being reshuffled. It almost seems Ancestry is making it a yearly tradition to perform their ethnicity updates in the Autumn. Or should I say a yearly marketing ploy? Either way this is already the third time in a row! Starting with the first distastrous make-over of Ancestry’s African breakdown in 2018. Things did get better though in 2019. My verdict of last year was: “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”. And really this assessment still stands also for this 2020 update. There have been a few positive changes, but nothing game changing

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Map and full listing of all the 12 African regions available on Ancestry after its 2020 update. Despite the renaming of  a few regions the only new region is “Southern Bantu”. This region will however be minimal or absent for practically all Trans Atlantic Afro-descendants.  Because of the restored “Ivory Coast/Ghana” region the West African breakdown is now more coherent than in 2019. However it still has several shortcomings…All in all nothing substantial to make up for the recent purge of smaller DNA matches.

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I find it disappointing that most of my suggestions for meaningful improvements (originally posted in 2018) have still not been taken up by Ancestry. Yet again this update seems to be centred mostly around providing greater regional resolution for Europe and Asia. The African breakdown seems to be merely a sideshow. The finer distinction to be made for Scottish ancestry is certainly striking but probably also overambitious.1 Such a focus is to be expected given that Ancestry’s customer database is overwhelmingly of European descent. While Asia probably represents a promising growth market. However the relative neglect of African & Afro-descended customer needs does go against Ancestry’s selfproclaimed goal to make their product experience inclusive for everyone. In my previous blog post I stated that Ancestry should seek to offer new tools geared to facilitate specialized research for Afro-descended customers. It should be clear that this update does NOT compensate for the loss of small African matches, earlier this month.

It is still my belief that each updated version as well as each separate DNA testing company should be judged on its own terms.2 For the sake of correct interpretation I have therefore yet again performed a comprehensive survey among 135 African Ancestry testers from all over the continent to evaluate the changes before and after this update. In addition I have also looked into a representative array of 50 updated results from across the Afro-Diaspora. These findings will be described in greater detail further below. Again for the most part no major changes. Which is why I will keep this discussion brief and only highlight the main outcomes:

  1. African breakdown for Africans before and after the 2020 update
  2. African breakdown for Afro-descendants before and after the 2020 update
  3. Is Ancestry getting sloppy?
    • When will we have genetic communities for West/Central Africa?
  4. Screenshots of African updated results

As always make an attempt to inform yourself properly without being overly dismissive. Despite shortcomings I do still think you can get valuable ancestral clues from Ancestry’s African breakdown. The macro-regional breakdown also to be taken into account to get a grasp on the greater picture. Instead of being preoccupied about the appearance of any surprising but minimal %’s. Which might very well disappear with the next update 😉 Such an approach to be combined with your remaining/salvaged African DNA matches, historical plausibility etc.. My previous discussion of the 2019 update may still offer helpful guidance. Ancestry’s FAQ is also useful:

Continue reading

African DNA matches reported for 30 Jamaicans on Ancestry

In this blog post I will analyze the African DNA matches being reported by Ancestry for 30 of my Jamaican survey participants.1 A follow-up to my previous blog post about 100 Jamaican AncestryDNA results (see this link). Most important finding arguably being that Nigerian & Ghanaian predominance in regional admixture (2013-2018 version) for Jamaicans is also reflected in their DNA matches. Notwithstanding recent updates on Ancestry 😉 Furthermore there is no longer any excuse NOT to be looking for African DNA matches. I found on average almost 30 African DNA matches for each one of my survey participants!!! There are plenty of Africans who have tested with Ancestry by now. So you only need to search for them and then you will be rewarded with greater insight and closer connection to your African heritage! See also these links:

Because I was given access to their profiles on Ancestry I was able to use my scanning and filtering method of DNA matches in Excel. Aside from African matches I will also be including Jewish and South Asian matches in my discussion. 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)

Stats (n=30)

All of my 30 survey participants received African matches. Also I was able to find 5 close African matches (>20cM)! On average 29 African matches were reported for each person. Around 80% of all African matches are connected to either Nigeria (16/29) or Ghana (7/29). The African admixture averages are based on the old 2013-2018 version of AncestryDNA. As I believe that despite shortcomings this version still offers the best fit for Jamaica’s known regional roots within Africa (see this link). Calculation of average & maximum shared DNA is based on the outcomes per survey participant. In all other tables below it will be calculated based on all DNA matches taken together.

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Table 2 (click to enlarge)

Afro 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 West African (Lower Guinea) related matches is 87% (755/861) of all African matches. The high number of especially Nigerian Igbo matches is quite striking. Undoubtedly due to very substantial ancestral connections. But possibly also a bit inflated within this overall overview. Reflecting a greater popularity of DNA testing among Nigerians as well as Ghanaians when compared with other Africans. Francophone & Lusophone migrants still tend to be  greatly underrepresented in Ancestry’s customer database. In particular it seems from Central Africa as well as Benin & Togo.

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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 African DNA matching patterns for Jamaicans in general. These outcomes may also provide valuable insight into the various ancestral components found within the Jamaican genepool. Contributing to answering major questions like: Do Jamaicans have more Nigerian or Ghanaian ancestry? In particular when aiming for complementarity by also taking into 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. Combine DNA matches with admixture analysis for more insight
  3. West African matches: as expected Nigerian and Ghanaian DNA matches were clearly most numerous. Only a subdued number of matches from Upper Guinea. This outcome is roughly in agreement with a predominant Lower Guinean macro-regional share of around 70% I calculated for 100 Jamaicans, based on admixture (see this chart).
  4. Central & Southeast African matches: quite low in number. In contrast with often substantial “Cameroon/Congo” scores being reported for Jamaicans. Interestingly Cameroon is relatively well represented.
  5. Other African matches: unexpected & uncommon. Higher odds of false positives but in some cases to be corroborated by distinctive admixture?
  6. Substructure: are there any group differences according to admixture level, “genetic community” or parish?
  7. Jewish & South Asian matches: disproportionately numerous whenever backed up by associated admixture (even in trace amounts!)
  8. Methodology: describing how I filtered the African & non-African DNA matches as well as the decision rules I applied when determining a plausible background for each DNA match.

Continue reading

Ancestry’s 2019 Update: Back on Track Again?

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!

Continue reading

100 Jamaican AncestryDNA Results (2013-2018)

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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Continue reading

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

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

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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