A few weeks ago I saw the Woman King and just like audiences all over the world I was blown away by the excellent cast and how beautifully the movie was shot. But most of all I love how a West African historical setting is the main focus in a Hollywood blockbuster! This movie has created a lot of attention and heated debate. Not least because of the justified critique of historical revisionism. Rest assured this blog post won’t feature yet another review in that line-up! However I will be providing an overview of resources and research findings which should be helpful to learn more about the historical and also genetic relevance of slave trade from the Bight of Benin.
The kingdom of Dahomey was located right at the center of the Bight of Benin which infamously was also known as the Slave Coast. The impact of slave trade from the Bight of Benin has been widespread across the Americas. For various groups of Atlantic Afro-descendants. But especially in terms of cultural retention there are some stand-out areas such as Brazil, Cuba, Haiti and Suriname. And genetically speaking also Barbados. Hopefully this blog post can serve as some kind of guidance for interpreting your own personal DNA results when wanting to trace back to Benin and neighbouring countries.
Before I continue I do want to quickly clarify my own stance on the Woman King controversy.1 When blogging about DNA test results on Ancestry and 23andme I have always warned against absolute dismissal. Because this may leave you empty-handed even when valuable insights are still to be gained! Instead from the start I have argued for a glass half-full mentality. Of course critical assessment is still required. But I firmly believe that you should always attempt to inform yourself about context, be aware of nuances and check your own bias, before passing judgement. The Woman King movie provides an excellent opportunity to do just that! In the last section of this blog post I will post many more useful links but a highly recommended starting point for more research is:
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 wayfor 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:
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:
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).
Figure 1 (click to enlarge)
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!
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).
In the remaining part of this blog post I will discuss the following:
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
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.
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:
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.
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.
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:
Considerations when dealing with DNA matches
Combine DNA matches with admixture analysis for more insight
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 Guineanmacro-regional share of around 70% I calculated for 100 Jamaicans, based on admixture (see this chart).
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.
Other African matches: unexpected & uncommon. Higher odds of false positives but in some cases to be corroborated by distinctive admixture?
Substructure:are there any group differences according to admixture level, “genetic community” or parish?
Jewish & South Asian matches: disproportionately numerous whenever backed up by associated admixture (even in trace amounts!)
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.
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:
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.
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.
“Cameroon/Congo” can also be partially indicative of southeastern Nigerian lineage (usually to a minor degree though, see this blog post)
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.
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:
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:
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!
“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.”
Unravelling the hidden ancestry of American admixed populations (Montinaro et al., 2015)
Own calculations based on “Unravelling the hidden ancestry of American admixed populations” (Montinaro et al., 2015)
“Although our sampling of Africans is incomplete, we see variation among groups in similarity to present-day populations from different parts of Africa. In all groups, the Yorubans from West Africa are the largest contributor, confirming this region [Lower Guinea] as the major component of African slaves” (Montinaro et al., 2015, p.3)
“In addition, more than 30% of the total slaves arriving in mainland Spanish America up to the 1630s came from Senegambia, and we accordingly find that the relative contribution from the Mandenka is higher in all areas historically under the Spanish rule.“(Montinaro et al., 2015, p.4)