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

Slave Voyages: not only Trans-Atlantic but also Intra-American!

This blogpost is mainly intended to announce a major overhaul for one of the most important sections on my blog:

The page referred to above is now featuring new screenshots taken from the invaluable Trans-Atlantic Slave Trade Database as well as the additional Intra-American Slave Trade Database. Reflecting the current state of knowledge. I am convinced that the data contained on that page can be very educational and useful for anyone wanting to learn more about their African roots. Just as long as you keep in mind inherent limitations and inform yourself about the relevant context. This kind of aggregated information is probably most useful on a population level.1 But also for your personal quest it can provide you with a very valuable starting point! In particular in order to judge the historical plausibility of any DNA test results you may have received. Not only regional admixture or haplogroups but also African DNA matches. And even DNA matches from across the Afro-Diaspora!2

***(click to enlarge)

Despite its limitations the Trans-Atlantic Slave Trade Database (TAST) is simply the most comprehensive and up-to-date resource available when wanting to look into Trans-Atlantic Slave Trade patterns. The website was updated in 2019. It now includes information about more than 36,000 Trans-Atlantic slave voyages! See also this recommendation by Henry Louis Gates.

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““If there were a Pulitzer Prize given for historical databases, the Transatlantic Slave Trade Database would win it, hands down,” says Gates, Alphonse Fletcher University Professor at Harvard.” (source)

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I myself have often relied heavily on the Trans-Atlantic Slave Trade Database as some sort of baseline. To establish historical plausibility within my ongoing research efforts on how personal DNA test results of Afro-Diasporans may already be in alignment with historical expectations. See also:

It can be very tempting to correlate slave trade records with population genetics or assumed ethnic/regional origins of Afro-descended populations. Given the absence of more straightforward information. But such an approach can hold many pitfalls. Even if the Slave Voyages database is deemed to provide nearly fully coverage for any particular country. This is because you cannot just simply assume that there will be a direct extrapolation from the data at hand. Reality is too complex regrettably. Several factors need to be taken into account. Mainly to do with incomplete knowledge about the demographic evolution of enslaved Africans and their descendants. See the updated section for more detailed discussion. This aspect might be most pertinent:

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  • Intra-American Slave Trade, Domestic overland Slave Trade and Post Slavery migrations have resulted in great deal of additional intermingling and diversification of African lineage. This is especially true for the USA and Brazil because of their continental size. But in fact also for most parts of the Caribbean and Latin America.

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Table 1 (click to enlarge)

Based on these estimates (taken from O’Malley, 2009),  Intra-American Slave Trade for North America was around 15%. The actual shares per state do show important variation. For Virginia and South Carolina this share of slave trade by way of the Caribbean is  quite minor: around 10%. However for other states it is more substantial. Do keep in mind though that Domestic (overland) Slave Trade is not taken into account. While actually going by sheer numbers this type of Slave Trade was most significant for the USA. An estimated 1 million enslaved African Americans (often with Virginia background) are known to have been victimized by the so-called Second Middle Passage (see this link).

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Obviously there will be other factors as well that could explain genetic results being disproportionate to what you might expect based on slave trade data. Substructure within any given Afro-descended population also being highly relevant. This is something which I have blogged about several times already and also in upcoming blog posts I will return to this important topic. Within the remaining part of this current blog post I will discuss the following:

  1. Trans-Atlantic Slave Trade Database
    • Newly added Portuguese & Spanish Slave Voyages (1500’s) corroborate Upper Guinean founding effect for many Hispanic Americans
  2. Intra-American Slave Trade Database
    • Disclaimers
    • Intra-American Slave Trade Patterns for the USA
  3. Final Passages: The Intercolonial Slave Trade of British America, 1619-1807 (G. E. O’Malley, 2014)

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

Why even small African matches matter!

On 14 July Ancestry announced that they will pull the plug on the smaller matches they have been reporting for years now. In particular distant matches which show a shared DNA amount within the range of 6cM – 8cM. For many people this may effectively wipe out more than half of their total matches. Furthermore for Afro-descendants this could mean the loss of many invaluable African matches! Overall I would estimate that on average in between 50-75% of all African matches might be erased by Ancestry’s update.1 In one big drastic operation… and with just a few weeks notice…

An alarming situation for anyone who is reliant on their DNA matches (incl. smaller ones) for their research. Fortunately there are some strategies to preserve your smaller matches. Especially by contacting them, grouping them, starring them or adding notes. For more details see this overview of various helpful blog articles:

An artisanal miner holds an uncut diamond in her hand in Kimberley

A South African woman is holding an uncut diamond in her hand (photo credits) African DNA matches can be as illuminating as diamonds. Even when small in size they can still be priceless! However carefull assessment is a MUST when dealing with potentially false matches because otherwise you’ll only end up chasing fool’s gold 😉

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In this blog post I will focus on the importance of smaller African matches. Something which has been revealed to me in my ongoing research on African DNA matches since 2017.2 Even when indeed many of them will be false matches. Precious informational value may still often be obtained. But it seems that this importance has not really sunk in yet with Ancestry or perhaps they have other priorities… Either way Ancestry’s announcement has been brutally abrupt and will catch many people by surprise. 

I hold no illusions about a complete reconsideration of this update (I love to be proven wrong though!). However I do hope the main arguments listed below may at the very least persuade Ancestry to delay their intended update. Even more so I wish that they wisen up and instead will implement tailor-made solutions which take into full account the diversity of their customer needs! If you agree please forward this blog post to Ancestry! For example in this suggestion box. See also the last part of this blogpost.

  1. Added value of small African matches
  2. Dangers of small African matches
  3. Appeal for true committment

 

Why even small African matches matter!

  • Afro-descendants face exceptional challenges when Tracing African Roots. Given the lack of a paper trail for the most part they have to go by any clues given! Out of sheer necessity the net has to be cast wide. An openminded and creative research approach is required. Both including but also going beyond genetic genealogy. All the while avoiding source snobbery in order to maximize any potential informational value.
  • Ancestry offers the biggest pond of African matches by far, when compared with other DNA testing companies. In great part because of its lower matching threshold which starts at 6 cM. This has been a precious resource for many which cannot be found elsewhere. It will be a tremendous loss when this pool of African matches will no longer be available or shrunk to a mere shadow of its former size!
  • Smaller matches may serve to reinforce more solid ancestral clues provided by related bigger matches (for example sharing the same meta-ethnic background). When combined with associated regional admixture and insights from other fields possibly leading to fruitful complementarity. See for example my survey of African DNA matches reported for 30 Jamaicans.
  • Small matches will indeed often be false matches or genealogically irrelevant but they may still be historically relevant (given correct interpretation). Leading to more insight of one’s African heritage within a greater timeframe. In particular when appearing with increased frequency. See for example my survey of African DNA matches reported for 50 Cape Verdeans.

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

The Mozambique connection on Ancestry & MyHeritage

Mozambique is a somewhat overlooked country of origin for many Afro-descendants. To be sure the Trans-Atlantic Slave Trade with Southeast Africa was relatively smaller in scope than with either West or Central Africa. Still according to most recent estimates it involved almost half a million people (see this overview from the TAST database). Especially for Brazilians, Haitians and Cubans Mozambican lineage might be considerable in some cases. Plus also the Indian Ocean Slave trade is to be taken into account. Which most likely resulted in a dispersion of a similar number of Mozambicans (see this overview, taken from this paper). Especially into South Africa and the Indian Ocean Islands: such as Mauritius, Réunion and Madagascar. But also to the Middle East and into South Asia and beyond even. For more details:

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Map 1 (click to enlarge

Kaartje MH

I found 12 most likely African matches for a person who is himself 1/2 Mozambican and 1/2 Portuguese. Most of these matches actually were likewise of mixed background. With the majority being from South Africa (6x). But also tellingly one single close match from presumably Pemba, Mozambique! MyHeritage provides a very useful filtering tool which allowed me to zoom into shared East African DNA segments among this person’s DNA matches.

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Then again some people might also have Mozambican ancestry due to recent migrations. In the last couple of months I have been given access to DNA results which reveal an already confirmed Mozambique connection for two people of mixed background. With very fascinating outcomes! As well as useful implications for other people wanting to learn more about their own possibly Mozambican lineage.

The first person is living in the Netherlands (like me). Both of his parents were born in Mozambique. But going back two generations his father’s grandparents are all of Portuguese descent. While his mother’s family has been living in Mozambique for as long as can be traced back. But her family tree does contain at least two persons who were born in India and migrated to Mozambique as well. When it was still under Portuguese rule. All in all a very fascinating tale of migration across several continents! This person tested with MyHeritage and he has been featured in a Dutch documentary series called “Identity”. I was actually honoured to also contribute to this documentary which was shot in my birth place Rotterdam. The actual day of filming being the 5th of July which happens to be Cape Verde’s Day of Independence! Highly symbolic for me therefore 😉 1 See also:

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Figure 1 (click to enlarge)

STP

These are the recently updated AncestryDNA results of a person whose father is from Mozambique. His Southeast African DNA is clearly indicated by his main regions, incl. also “Eastern Bantu”! Another intriguing aspect is that this person actually also has a Cape Verdean connection by way of São Tomé & Principe. This is revealed by a very distinctive score of 6% “Senegal”. Probably also to be combined with the “Portugal” & “Spain” scores. Highlighting that regional admixture DOES matter!

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The other person is a DNA cousin of mine on Ancestry whose mother was born in São Tomé & Principe while his father is from Mozambique. I am related to him by way of a mutual Cape Verdean relative who migrated to São Tomé & Principe as a contract labourer during the first half of the 1900’s. São Tomé & Principe is a former Portuguese colony just like Cape Verde and Mozambique. But nowadays it is an independent island state located nearby Gabon in the Gulf of Guinea. Just like Angolans and Mozambicans many Cape Verdeans ended up settling in São Tomé & Principe during the Portuguese colonial time. Notoriously being employed under very harsh circumstances on the cocoa plantations of São Tomé & Principe. It therefore still has a sizeable community of Cape Verdean descendants. Their continued longing for their motherland has been made world famous by the song “Sodad” by Cesaria Evora (see this video clip).

This blog post will describe the DNA results of both persons. Seeking to demonstrate in particular how correlating regional admixture analysis with DNA matches can be rewarding and mutually reinforcing in many cases. In addition I will also discuss my experience with MyHeritage. As I have myself not tested with this company. And so this was the first time I had the chance to get acquainted with several of its features. Allowing me to also make some cross-comparisons with Ancestry.

  • Mozambican Connection on MyHeritage
  • Mozambican Connection on Ancestry
  • Comparing Ancestry with MyHeritage
    1. MyHeritage is distorting Central & Southeast African DNA
    2. Ancestry offers greater potential to find African matches
    3. MyHeritage provides more advanced filtering tools

 

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).

***

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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