“Nigeria East-Central” on Ancestry: a wasted opportunity!

So-called “Nigeria East-Central” scores are either absent or minimal for most people. Why on earth did Ancestry think this would be a good idea?

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Recently Ancestry introduced a new region called “Nigeria East-Central”. The first addition to their West African breakdown since their truly pioneering update in 2013.¹ Sadly this novelty is a major let-down. Ancestry could and should have done so much better! They had more than enough time to prepare for it…A further specification of Nigerian DNA has been on the wishlist for many people. I have also been advocating this for several years already.

In order to assess Ancestry’s latest update I have done a survey among 50 people from several parts of the Afro-Diaspora. 80% of my survey group (40/50) did not receive any “Nigeria East-Central” score at all. All group averages are barely 1% (see this overview). The highest individual score in my survey was only 3% for a Haitian. Don’t get me wrong: such minimal scores can still provide valid indications. Which I will also discuss in this blog post. But these paltry statistics are a clear sign of how little added value this new region brings. 

This first major expansion of Ancestry’s West African breakdown since 2013 should have been done in a meaningful and beneficial way for Atlantic Afro-descendants. Relying on historical relevance when deciding on new regions. Frankly anyone with some basic googling skills would know already! Southwest Nigeria (centered on Yorubaland) and southeast Nigeria (centered on Igboland) are obviously going to be first choice when wanting to specify Nigerian DNA. As demonstrated by 23andme in their update earlier this year. Instead Ancestry completely passed over these pivotal regions of Nigerian origins for the Atlantic Afro-Diaspora… Such a wasted opportunity! See also:

• Ancestry’s 2022 update: some bright spots, but too little too late!
• New Update on 23andme: Ethnic Group Matches within Africa! (part 1) (part 2)

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Contents of this blog post:

1. How to interpret your “Nigeria East-Central” scores
   • Ancestry should reveal the ethnic backgrounds of its “Nigeria East-Central” samples!
   • Historically relevant for Atlantic Afro-descendants?
   • Summary in 11 steps.
2. When will Ancestry finally create Nigerian Genetic Communities?
   • How many Nigerian DNA samples does Ancestry have?
   • Always be cautious with ethnic implications in DNA testing!
3. Screenshots of “Nigeria East-Central” scores

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New Update on 23andme: Ethnic Group Matches within Africa! (part 1)

Earlier this month 23andme released its most recent update which could very well signal the start of a truly game-changing feature for zooming into ethno-linguistic African lineage.¹ Going beyond the broad regional admixture categories such as “Nigerian” and “Senegambian & Guinean”. Which are already quite useful in fact. However by now providing much more granularity 23andme is really stepping up its game! For more details read this announcement by 23andme:

• 23andMe Adds New African Ethnolinguistic Groups to Ancestry Composition (23andme, 2022)

Of course this new feature on 23andme, based on matching strength, is not perfectly flawless or without its inherent limitations. And to be sure the possibility of learning more about the specifics of your African ancestry by looking for African DNA matches has been around for several years already (see this overview). However the novelty of this update lies in the robust manner in which your DNA is being compared to a wide array of 25 historically plausible populations to indicate the ethnic origins of (some) of your African ancestors. This is an ambitious endeavor which has been greatly anticipated by so many people throughout the years! Bringing to life a regional African breakdown which was often experienced as being too basic and incomplete.² Although from my assessment actually many valuable insights can also be derived from regional admixture, when interpreted correctly (see this overview).

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Figure 1 (click to enlarge)

A representative selection of updated 23andme results for Africans across the continent. I have seen more than 50 updated results from mainland Africa so far. Based on those results I am quite sure that this feature is pretty accurate. Because usually the outcomes are corresponding with the known ethnic backgrounds of African 23andme testers. As always unrealistic expectations about “100% accuracy” should be avoided. And to be sure 23andme doesn’t always “get it right”. But this update certainly can be considered as a huge step forward in pinpointing African lineage!

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Despite a few shortcomings I am very excited about this update on 23andme! Because based on more than 50 updated results for Africans I am quite impressed with the accuracy of this tool. Also the results I have seen for 50 Cape Verdeans and 100 African Americans are actually in line with historical plausibility. This blogpost series is therefore intended as a first introduction. In future blogposts I will follow-up with more details on the implications of these ethnic group matches within Africa! In fact I will also edit this blogpost itself with more information in the upcoming weeks (especially footnotes). So you might want to check that out too by revisiting this blogpost.

Right now the odds of obtaining one of the 25 ethno-linguistic groups are rather low for most people. Depending also on your background. For many people 23andme is simply not able to detect a sufficient level of matching strength. Which is inevitable given the limitations of 23andme’s African reference database.³ Understandably this may come as a big disappointment. However don’t despair because this update is a work in progress and upcoming updates will eventually reach more people!

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Table 1 (click to enlarge)

This chart shows that only 21 out of 100 of my African American survey participants received any ethnic group match (a few received more than 1). Hence the odds of receiving this update (~20%) are not that high. But still it is already a clear improvement when compared with the odds of receiving a match for an African country by way of 23andme’s Recent Ancestor Location tool. Based on a previous survey of mine this was only 3% for African Americans (see this overview).

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

1. Disclaimers
   • Not intended to be conclusive! Ethnic identities are fluid and contextdependent.
   • Keep in mind implied timeframe.
   • Focus on complementarity of DNA matches and regional admixture
   • Educate yourself on historically plausible ethnic origins
2. How accurate is this update?
   • Updated results for 50+ Africans

In part 2 of this blogpost I will discuss my survey findings for 100 African Americans and 50 Cape Verdeans. Furthermore I will also post screenshots of updated results from other parts of the Afro-Diaspora.

• New Update on 23andme: Ethnic Group Matches within Africa! (part 2) 

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

• Genetic Consequences of the Transatlantic Slave Trade in the Americas (Micheletti et al., 2020)
• Supplemental Data Micheletti et al, 2020
• Table S7. Mean Ancestry Composition for the Research Cohort (main source for comparison) 

My own survey findings based on 23andme and AncestryDNA results

• Afro-Diaspora AncestryDNA results: A Comparison (Fonte Felipe, 2016)
• Update: Afro-Diasporan AncestryDNA Survey (part 1) & part 2) (Fonte Felipe, 2018)
• 23andme’s African breakdown put to the test: Afro Diaspora edition! (Fonte Felipe, 2021)

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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:

• 350 African American AncestryDNA results (2015)
• 200 African American 23andme results (2018/2019 version)

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

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:

• African DNA Matches Service
• How to find those elusive African DNA matches on Ancestry

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:

• Spreadsheet with DNA matching patterns specified for 30 Jamaicans

Table 1 (click to enlarge)

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)

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.

Igbo, Yoruba or Hausa-Fulani? Nigerian AncestryDNA results 2013-2018

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:

• Nigerian AncestryDNA results

Table 1 (click to enlarge)

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)

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.

DNA matches reported by 23andme for 75 Africans

Wishing to share the vibranium 😉 I have created a new page featuring the DNA matches reported by 23andme for 75 Africans, all across the continent. These results were collected by me in 2015 when 23andme’s Countries of Ancestry (CoA) tool was still available.

My survey results might have limitations in several regards but I do believe these African CoA results can still reveal relevant tendencies in DNA matching. I intend to compare these preliminary matching patterns eventually with my more recent findings for Africans who tested on Ancestry. I provide detailed background info as well as screenshots of the individual results on this page:

• Countries of Ancestry results for 75 Africans

(click to enlarge)

AncestryDNA Results Across the Diaspora

In 2013 AncestryDNA updated their Ethnicity Estimates to include a very detailed breakdown of West African ancestry (see this article). Soon afterwards I started collecting AncestryDNA results in an online spreadsheet in order to conduct a survey of the African regions being reported by AncestryDNA, among both African Americans as well as other Afro-descended nationalities. Attempting to establish how much the AncestryDNA results on an aggregated group level can already (despite limitations of sample size) be correlated with whatever is known about the documented regional African roots for each nationality.

Rumour has it that AncestryDNA will shortly start rolling out a new update of their Ethnicity Estimates. So it seems the time is right to finalize my survey. The sample size for most groups appears to be suffciently robust now to allow a meaningful intercomparison. In the AncestryDNA section of my blog (see the menubar) you can find a detailed summary of my survey findings based on 707 results for 7 nationalities:

• “Afro-Diaspora AncestryDNA results: A Comparison”

Gathering all the results was a great learning experience. It has been a very satisfactory project! My survey report merely represents my personal attempt at identifying generalized, preliminary and indicative patterns on a group level inspite of individual variation. Everyone has a unique family tree of course first of all.

I would like to thank again all my survey participants for sharing their results with me. I am truly grateful for it!

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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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Louisiana: most African diversity within the United States?

Louisiana Slave Database 1719-1820

SUMMARY

Number of slaves with origin specified 29,769
American born (“Creole”) 13,618 (45% of total)
African born 16,099 (54% of total)
African specified ethnically 8,994 (30% of total)

TOP 3 BREAKDOWN OF AFRICAN BORN SLAVES

Congo (Central Africa) 2,988 – 33% of African specified
Mandinga (Upper Guinea) 922 – 10% of African specified
Mina (Ghana, Togo, Benin) 628 – 7% of African specified
Source: Slavery and African Ethnicities in the Americas: Restoring the Links (Hall, 2005).

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“Gwendolyn Midlo Hall’s remarkable relational database of Louisiana slaves and freedmen (1719-1820), which contains records of over 100,000 enslaved people, includes nearly 9,000 individual Africans by specific ethnicity. The database was first published in 2000 as a CD-ROM, and it is now available free on the Internet. The database is derived largely from notarial and ‘‘succession’’ (probate) records, mostly in French, in which slaves often self-identified their ‘‘nations’’ or ‘‘countries’’. There are 217 different ethnicities recorded, of which 96 have been identified, and a further 121 (comprising 152 individuals) which have not been identified. Of those identified, just 18 ethnicities account for over 96% of the Africans in the Louisiana records. In addition, within that set of 18 principal ‘‘nations,’’ the seven most common (in order, Kongo, Mandingo, Mina, Senegal/Wolof, Igbo, Bamana, Chamba), comprise over three-quarters of the sample. The single most numerous ‘‘nation’’ in the dataset was Africans from Kongo (nearly 3,000 individuals), the vast majority of whom arrived in the late eighteenth and early nineteenth centuries” (Chambers, 2008, pp.335-336).

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For a direct link to this extremely fascinating and online searchable database created by Gwendolyn Midlo Hall see below:

Louisiana Slave Database 1719-1820

A full overview of the 18 most frequently named African origins can be seen in the remaining part of this blogpost in which i will attempt to provide more details and context about Louisiana’s African diversity.

The Igbo Connection for Virginia & Virginia-Descendants

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Trans-Atlantic Slave Trade Database (2010) (http://www.slavevoyages.org/)

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Source: “Rejoinder – The Significance of Igbo in the Bight of Biafra Slave-Trade- A Rejoinder to Northrup’s Myth Igbo ” (D.B. Chambers, 2002)

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Domestic Slave Trade routes from Virginia to the Deep South

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” at least 60% of Black Americans have at least 1 Igbo ancestor” (Dr. Douglas B. Chambers during Radio Interview (recommended listening)

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Jamaican maternal lineages trace back mostly to Ghana?

Source: “Interdisciplinary approach to the demography of Jamaica”, (Deason et al., 2012).

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“In line with previous findings, the matriline of Jamaica is almost entirely of West African descent. Results from the admixture analyses suggest modern Jamaicans share a closer affinity with groups from the Gold Coast and Bight of Benin despite high mortality, low fecundity, and waning regional importation. The slaves from the Bight of Biafra and West-central Africa were imported in great numbers; however, the results suggest a deficit in expected maternal contribution from those regions.” (Deason et al., 2012)