West Africa (part 1)

An updated version (3.0) of Ancestry Composition has been rolled out by 23andme in January 2019 for all its customers. FINALLY it also includes a meaningful African breakdown! I have always believed that the best way to find out about the predictive accuracy of any particular DNA test or update is to look at the results of people who actually know their (recent) origins. In order to improve correct interpretation I have therefore started a survey among African DNA testers. Using their group averages as some sort of rudimentary benchmarks so to speak. Of course also some basic knowledge about DNA testing (in particular 23andme’s reference populations and methodology) as well as historical context will remain essential to really get the most out of your own admixture results!Follow the link below to see my spreadsheet which contains all the individual results I used for my survey findings:

Twelve new African regions on 23andme

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Figure 2 (click to enlarge)

AC-33-Africa.001

Nine specific regions and 3 broadly macro-regions are now available on 23andme’s Ancestry Composition to describe your origins across the African continent (aside from “Broadly Sub-Saharan African” and “North African & Arabian”). The country name labeling is not to be taken too literally, as always. But it is actually quite indicative if you simply take it as a proxy and also take into account surrounding countries. Despite being less specific it will still also be helpful to distinguish between macro-regional areas within Africa: “West African” versus “Central & Southern East Africa” versus “Northern East Africa”, see also table 1.

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On this page I will be featuring the individual screenshots of West African 23andme testers (from Senegal to Ivory Coast). In the second part I will post screenshots from Ghana, Benin and Nigeria. Almost all results included in my survey have been shared with me by the DNA testers themselves.Some results were also kindly shared with me by friends. And a few results were collected by me from social media. Naturally I verified the background of each sample to the best of my capabilities but I did not have absolute certainty in all cases. I like to thank all my African survey participants for having tested on 23andme and sharing their results with me so that it may benefit other people as well!

For screenshots of the individual results from other parts of Africa see also:

For screenshots of West African 23andme results before the 2018/2019 update see this page (published in 2015):

At times I will also feature screenshots of people of mixed background. Usually 1 parent being from a specific African country and 1 parent being from Europe or elsewhere. But also Africans with 1 European grandparent, 1 great-grandparent etc..  In order to make the African composition results inter-comparable between all my survey participants I have scaled the African part of 23andme’s breakdown to 100% for people of mixed background. I actually find that especially in these mixed cases 23andme’s update really shows it added value. As most of the times also the known African background of mixed people is fairly well described.

p.s. I will usually only feature screenshots of the African breakdown. You will notice it will often not add up to an expected 100%. In most cases this is because of a well known “bug” in 23andme’s Ancestry Composition. Which causes people of “100% African” descent to show trace levels of non-African admixture or “unassigned” ancestry. This can generally be considered “noise”, i.e. reflecting an artefact of the DNA test. Hopefully it will be fixed with the next update. In some other cases though the individuals will have genuine additional non-African ancestry. Which might however be “native” to Africa still. Especially if it is related to North African(-like) DNA. Otherwise it might reflect historical geneflow from outside of Africa within the last 500 years or even earlier.

p.p.s. Sometimes I might draw comparisons with the former African breakdown on AncestryDNA. Unless stated otherwise I will always be referring to the old version of AncestryDNA, current between 2013-2018! As I believe that Ancestry’s last update of September 2018, unlike 23andme’s current update, has not been beneficial for Africans and Afro-descendants. See also:

West African group averages

Table 1(click to enlarge) 

WA group averages

This table contains my main survey findings. It illustrates how 23andme’s new African breakdown is performing for West Africans. Click on this link for an up-to-date version of this table. Although less specific do take notice how also the macro-regional breakdown (West African vs. Central & Southeast African vs. Northeast African) is quite accurate!

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The statistical data displayed in table 1 is evidently based on a minimal sample size but still pretty comprehensive already. A few West African countries are not yet being covered (such as Togo and Niger). Furthermore all of the included countries themselves harbour a multitude of ethnic groups. Right now however I can only make statistical calculations for a few well represented ethnic groups within 23andme’s customer database. A greater degree of genetic diversity and individual variation might therefore be expected across West Africa and also within the listed countries.

Eventhough only preliminary statements should be allowed at this stage I still suspect that these group averages are already a reasonably good approximation of the main regional components to be found within the genepool of this part of Africa. According to 23andme new African breakdown obviously 😉 . The group averages I have calculated so far often exceeding 70% for each West African nationality and at times even reaching 90%! Although admittedly intermediate countries such as Mali and Benin are somewhat less well captured right now. Because 23andme does not have separate categories in place for these countries, unlike AncestryDNA.

The “Senegambian & Guinean” region is strongly predictive for actual Senegalese, Gambians and Guineans (Bissau & Conakry). Group averages were in between 76% and 88%. On a whole rather consistent scores of around 80%. But the highest individual score actually being 95%! Similar in scope to the “Senegal” region on AncestryDNA (prior to the 2018 update!) but probably a bit more predictive, judging from my survey results. In particular for Guineans.

My 25 Cape Verdean samples are over 70% “Senegambian & Guinean”, on average. As usual I have applied a scaling formula in my survey whereby the African breakdown of mixed persons counts as 100%.3 This outcome is once more confirming the overwhelmingly Upper Guinean roots for Cape Verdeans! I intend to expand my Cape Verdean survey group to 100 samples at which time I will publish my findings in greater detail. See below for a link to my spreadsheet with the individual Cape Verdean 23andme results. As well as a link to my previous analysis based on 100 Ancestry results (group average of 62% “Senegal” & 13% “Mali”):

The ancestry compositions of Fula people changed quite considerably. In particular in regards to formerly quite substantial (>10%) “North African” and even “East African” scores being reported. Indicative of the uniqueness of Fula genetics. But after the update these scores have almost completely disappeared. This may be considered a loss of specification I suppose. Especially from a perspective in which ancient lineage also matters. However right now a very convincing level of around 85% “Senegambian & Gambian” has surfaced. Possibly because 23andme included Fula samples from Guinea Conakry in their reference database.  

It is quite impressive how 23andme is now able to distinguish between the Senegambian and Nigerian origins of Hausa-Fulani people. And even for one single Sudanese Fula, a.k.a. Fellata, sample in my survey group! The new “Senegambian & Guinean” region functioning as a marker of Fula lineage for them. An outcome which was formerly also obtained on Ancestry (see this spreadsheet). Testimony of eastbound Fula migrations from Guinea across the Sahel into northern Nigeria and then onwards to Sudan!

However aside from “Senegambian & Guinean” also other regions are frequently reported for my survey participants from this part of West Africa. Either as minor genetic components but often also with substantial amounts, even in the double digits. Nearly always neighbouring and genetically overlapping West African regions are involved though.  In a way these main secondary regions help make each nationality/ethnicity more recognizable. Rather than just focusing on their primary regions which are in no way unique to any given country!  I find it quite reassuring that almost all of my West African samples are showing up as above 90% West African (excl. unassigned & broadly “SSA”). Because this implies that whenever an unexpected regional score outside of West Africa is reported you can be more sure that it is in fact indicative of something distinctive.

Especially Gambian results showed more variation. The lowest score for “Senegambian & Guinean” was 43.7% for a Gambian survey participant. Instead this person had “Ghanaian, Liberian & Sierra Leonean” in first place with 49.2%. Other Gambian results in my survey actually also showed quite substantial “Ghanaian, Liberian & Sierra Leonean” scores of around 20%.  I suppose this outcome is similar to how the “Mali” region on AncestryDNA often also showed up strongly as a secondary region for Senegambians & Guineans (before Ancestry’s update).

Although I only have one sample to go by (with one European parent!) it seems likely that Malian ancestry falls in between “Senegambian & Guinean” on the one hand and “Ghanaian, Liberian & Sierra Leonean” on the other. Actual ethnic background probably determining the balance. Unlike AncestryDNA there is no separate “Mali” region on 23andme after all. Which necessitates a combination of two neighbouring and partially overlapping regions.

So one might say that Upper Guinean DNA is not fully covered by “Senegambian & Guinean”. In particular from the interior into western Mali and the southern fringes beyond Guinea Conakry. Still this region does reach a substantial level of around 20% among (northern) Sierra Leoneans! Also I find it reassuring that among the main core of my Senegambian & Guinean survey participants there is hardly any overlap with “Nigeria”, let alone any non-West African region! Quite tellingly the only notable (and very atypical) “Nigerian” score was received by a Gambian survey participant whom I suspect is of partial Aku (=Krio) descent.

It is striking but quite logical (given geography) how native Sierra Leoneans (excl. Krio) hardly show any detectable “Nigerian .But instead they do score considerable (>10%) amounts of  “Senegambian & Guinean” as secondary region. Especially people from northern Sierra Leone. It is the opposite for Ghanaians who tend to have negligible “Senegambian & Guinean” but instead do score significant (>15%) amounts of “Nigerian”. Liberians and Ivorians being somewhat in between. A very useful outcome because this implies that substantial amounts of “Nigeria” as well as “Congolese” can be useful to indicate Krio and Americo-Liberian background. “As well as related Aku lineage among Gambians. The absorption of Recaptive Africans from southern Nigeria but also other places (such as the Congo) leaving a distinctive genetic imprint among certain population segments of Sierra Leone, Liberia and Gambia. Quite impressive that 23andme’s new African breakdown is now able to single it out.

These extra regions may be unexpected at first sight for people who according to their own knowledge are “100%” Senegalese, Guinean, Liberian etc.. Taking these results at face value can therefore be misleading without correct interpretation. The disclaimers I already mentioned above as well as the links provided below should provide sufficient clarification. As actually this outcome does overall still make sense. In short the advise would be to: don’t overfixate on the labeling of ancestral categories! Rather try to maximize informational value despite imperfections. In fact this does not only go for 23andme but any kind of admixture analysis. In order to avoid jumping to premature conclusions I highly recommend that you atleast browse through some of the topics mentioned in the following links:

“Senegambian & Guinean”: good proxy for Upper Guinean DNA 

Map 1 (click to enlarge)

Senegambian & Guinean

Quite accurate indicator of Upper Guinean DNA. Similar to the “Senegal” region on AncestryDNA (prior to the 2018 update!). But probably somewhat more predictive. I will publish a separate page with my Cape Verdean survey findings eventually. Not shown in the map but actually all my survey participants of Fula descent in Nigeria, Niger and Sudan also received significant “Senegambian & Guinean” scores. Confirming their western origins, from the historical Fula heartlands of Futa Tooro in Senegal & Futa Djallon in Guinea Conakry (see this page for several maps on Fula migrations).

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CAPE VERDE (Santiago)

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CV

These are the updated results of a DNA cousin of mine. My 25 Cape Verdean samples are over 70% “Senegambian & Guinean”, on average. As usual I have applied a scaling formula in my survey whereby the African breakdown of mixed persons counts as 100%. This outcome is once more confirming the overwhelmingly Upper Guinean roots for Cape Verdeans! I intend to expand my Cape Verdean survey group to 100 samples at which time I will publish my findings in greater detail. Follow this link to see my spreadsheet with the individual Cape Verdean 23andme results. As well as this link to my previous analysis based on 100 Ancestry results (group average of 62% “Senegal” & 13% “Mali”). Also take note of how “Cabo Verde” is accurately pinpointed as ancestral location. However a far more fitting place would be below “Senegambian & Guinean” rather than under “Broadly West African”!

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SENEGAL (Sereer?)

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SEN - Sereer

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SENEGAL (Wolof?)

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SEN - Wolof

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SENEGAL (Mandingue?)

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SEN - Mandingue

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SENEGAL (?)

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SEN - inconnu

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SENEGAL (1/2 Wolof? & 1/2 French)

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SEN - Halvie Wolof

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SENEGAL (1/4 French?)

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SEN - driekwart

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SENEGAL (multi-generationally mixed?)

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SEN - halvie FR

This person is the mother of the person whose results are featured directly above. They have been sharing profiles with me on 23andme for almost ten years now! And it has been very insightful to see how their results changed with each update. I do not have full knowledge on their background. But I do know that they were both born in Senegal. Given that the %’s are somewhat off for a person with one 100% European parent I suspect mixed-race lineage may go back a couple more generations. Senegal has a long history of mixed-race communities. Not only due to French colonization (see this page). But actually also due to previous Portuguese presence & Cape Verdean migrants (see this page for references)!

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GAMBIA (?)

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GAM - unknown1

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GAMBIA (Mandinka or Soninké?)

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GAM - Mandinka Sarakolé1

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GAMBIA (Mandinka or Soninké?)

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GAM - Mandinka Sarakolé2

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GAMBIA (partially Aku?)

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GAM - part AKu

Regrettably I do not have any details on this persons background. However notice the “Nigerian” score of 15.4% . I therefore highly suspect this person might have partial Aku lineage. Which might be common especially for people from the capital Banjul. Such a high ‘Nigerian” score has been very atypical sofar among my other Senegambian & Guinean survey participants. For whom it was generally <1%. But it would make sense for someone of partially Aku lineage as afterall it is known that many of them also have distant Yoruba and/or Igbo lineage, similar to the Krio from Sierra Leone.

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GAMBIA (?)

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GAM - unknown

Quite atypical outcome for this Gambian person (of unknown ethnic background) to show “Ghanaian, Liberian & Sierra Leonean” in first place instead of  “Senegambian & Guinean”. The only one from my Senegambian survey group sofar. It is probably a deviation caused by a markedly different ethnic background from the samples contained within 23andme’s reference database.  Perhaps again Aku lineage but possibly also because this person’s origins are tending more so towards Mali, which does not have a separate region on 23andme.

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GAMBIA (1/2 Gambian & 1/2 Jamaican)

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GAM & JAM

Very interesting results for this person with one parent from Gambia and one parent from Jamaica. I will eventually also start a survey for Jamaican updated 23andme results. And it will be insightful to compare then. Given my previous AncestryDNA survey among Jamaicans I am pretty confident that such a breakdown will be extremely rare among people of fully Jamaican descent. As their Senegambian lineage  tends to be very diluted. Highlighting how regional admixture CAN be very useful! Notice also the correct ancestral location of United Kingdom being assigned!

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GUINÉ BISSAU (Mandinga)

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GB - Mandinga

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GUINÉ BISSAU (1/2 Russian)

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GB - halvie

Very impressive result for this person with one parent from Guinea Bissau and one parent from Russia. Perfect illustration of how regional admixture CAN be very useful both for the African and European breakdown. Notice also the correct ancestral location of Russia being assigned! Hopefully with greater expansion of 23andme’s database eventually also Guiné Bissau will be specified for this person’s African side.

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FULA (Guinea Conakry)

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GC - Fula (2)

The ancestry compositions of Fula people have changed quite considerably. In particular in regards to formerly quite substantial (>10%) “North African” and even “East African” scores being reported. Indicative of the uniqueness of Fula genetics. But after the update these scores have almost completely disappeared. The minor “European” scores very likely to be a mislabeled remnant. As North Africans now also tend to receive high scores of South European %’s on 23andme (due to genetic similarity). This may be considered a loss of specification I suppose. Especially from a perspective in which ancient lineage also matters. However right now a very convincing level of “Senegambian & Gambian” has surfaced. Also notice “Guinea” being mentioned as ancestral location! Possibly because 23andme included Fula samples from Guinea Conakry in their reference database.

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FULA (Guinea Conakry)

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GC - Fula

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FULA (Senegal)

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FULA (SEN)

Interesting to compare this Fula result from Senegal with the previous two from Guinea Conakry. The amount of North African(-like) DNA is markedly higher.  It was only 0.5% and 0.2% for the ones from Guinea. Although again also the “European” %’s should be added for good measure. Notice also the decreased level of “Senegambian & Guinean” and the considerable “Ghanaian, Liberian & Sierra Leonean” score. Probably an outcome caused due to the inclusion of Guinean Fula samples in 23andme’s reference database while Senegalese ones have been left out sofar.

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MALI (1/2 Mandé, 1/2 British)

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MALI - halvie

I have no confirmation but this persons Malian parent is probably Bambara while his other parent is from the United Kingdom (which has correctly been identified as ancestral location!).  More Malian results should be forthcoming to obtain firmer ground. However based on this single breakdown it may already be assumed that Malian DNA is not adequately covered yet by 23andme. Instead it has to be described by two neighbouring and partially overlapping regions. Although also some “Nigerian” is appearing. Probably just an indication of how this person’s DNA is somewhere in between 23andme’s current West African sample constellation.

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“Ghanaian, Liberian & Sierra Leonean” also found in surrounding countries

Map 2 (click to enlarge)

Ghanaian, Liberian & Sierra Leonean

Goes beyond the three countries mentioned in the labeling. As in fact this region is also very descriptive of DNA found in Burkina Faso and naturally the Ivory Coast. Because of the inclusion of Sierra Leonean samples somewhat overlapping into Upper Guinea. But also to the east reaching considerable scores in Benin (30%) and even among two of my northern Nigerian samples (17%). Somewhat unsatisfactory grouping therefore. Especially given the need of distinction between origins from the Gold Coast, Wind Coast and Bight of Benin for Afro-Diasporans. Still works pretty good for especially Sierra Leoneans and Liberians. Also helpful to single out Krio & Americo-Liberian lineage!

SIERRA LEONE (Mende & Temne)

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SL -(half Temne, half Mende)

This screenshot as well as the one below features the initial name chosen for the “Ghanaian, Liberian & Sierra Leonean” region: “Coastal West African”. It has rightfully been withdrawn by 23andme. Because in fact also origins from interior West Africa (Burkina Faso, Mali, northern Nigeria) are covered by this region. Then again the current country name labeling is also a bit misleading. It illustrates the dilemma of adequate regional labeling.

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SIERRA LEONE (Mende & 1/4 Liberian)

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SL - Mende Liberian

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SIERRA LEONE (Limba?)

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SL - Limba

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SIERRA LEONE (Mandingo & Kissi)

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SL - Mandingo & Kissi)

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SIERRA LEONE (Temne?)

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SL - Temne

Take note of the considerable “Senegambian & Guinean” score being reported. In fact several other Sierra Leonean survey participants scored above 15% for this region. Even when it seems that 23andme used quite a diverse array of Sierra Leonean reference samples (Mende, Temne, Limba).

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SIERRA LEONE (Krio?)

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SL - part. Krio

This person is quite likely of (partial?) Krio lineage. Not only because of his surname but also because of this  atypical breakdown when compared with the previous ones. Take note especially of the increased “Nigerian” amount! The previous breakdowns from Sierra Leone hardly showed any “Nigerian” beyond 1%! However substantial Yoruba and or Igbo ancestry makes perfect sense for the Krio from Sierra Leone. Who may also be seen as Afro-Diasporans, even when located in Africa itself!

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SIERRA LEONE (1/2 Krio & 1/2 British)

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SL - Krio halvie

This person has confirmed to me to have one British parent (the UK is correctly being assigned as ancestral location). And also a Sierra Leonean Krio parent. You might never have guessed though given the almost absent score for “Ghanaian, Liberian and Sierra Leonean”! Instead this person’s African breakdown is very much dominated by “Nigeria”! Quite amazing how this region may help to single out Krio lineage and even specify it further to distant Yoruba or Igbo ancestors. Although possibly “Congolese” might also serve as an indicator of Krio lineage for other Sierra Leoneans.

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LIBERIA (?)

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LIB - unknown

Very convincing “Ghanaian, Liberian and Siera Leonean” score. The highest among my Liberian survey participants. Still also intriguing to see 0.6% being reported for  “Filipino & Austronesian”. It could obviously just be noise! But from what I have seen (among more than 170 African results) such noise levels on 23andme are usually restricted to 0.1%. I have actually additional reason to suspect this minimal amount of DNA could still possibly be indicative of one single distinctive ancestor. Perhaps a Malagasy lineage carried over to Liberia by way of a North American descended Americo-Liberian? This extra clue being provided by this person’s matches on the former Country of Ancestry tool (see Liberian 2 on this page). The small but still noticeable amount of “Nigerian” also being indicative of such a Krio scenario.

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LIBERIA (Kpelle, Lorma, Mandé)

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LIB - Kpelle

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LIBERIA (part. Americo-Liberian?)

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LIB - part Americo

Quite convincing “Ghanaian, Liberian & Sierra Leonean” score. Also Liberia is correctly assigned as ancestral location (which happened 2/6 times for my Liberian survey participants). Still the rather elevated levels of “Nigerian” and especially “Congolese” might indicate this person has some partial Americo-Liberian lineage, a.k.a. “Congo” or “Recaptives”. This person’s DNA matches might possibly provide additional clues. With a greater Liberian sampling it will be very interesting to see to what degree these lineages from outside of Liberia have been dispersed across the general population.

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LIBERIA (1/4 Lebanese)

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LIB - kwart Leb

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LIBERIA (Americo-Liberian)

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LIB - part. Americo

This person of confirmed Americo-Liberian descent is showing a predominant “Ghanaian, Liberian & Sierra Leonean” score as well as a correct assignment of “Liberia” as ancestral location. But otherwise this breakdown would not look that out of place in the West Indies I suppose. Both “Nigerian” and “Congolese” being quite noticeable, even if clearly subdued. And also given the minor European admixture.

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LIBERIA (Americo-Liberian)

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LIB - Americo

Another person of confirmed Americo-Liberian descent. This time with a much more diverse African breakdown. The “Congolese” amount of 18.1% easily being the highest I have observed among my West African survey participants. Also no longer “Liberia” being mentioned as ancestral location. Given the more prominent scores for both “Nigeria” and “Congolese” I would imagine this time this breakdown might also be mistaken for an African American one, aside from also the West Indies.

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IVORY COAST (?)

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CIV- inconnu1

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IVORY COAST (1/8 French?)

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CIV - octoon FR

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IVORY COAST (Malinké?)

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CIV - Malinke

Take notice of the nearly 20% score for “Senegambian & Guinean“. Given this person’s most likely Malinké background not that surprising. In fact also part of the predominant “Ghanaian, Liberian & Sierra Leonean” score could actually be indicative of northern origins from Mali.

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IVORY COAST (?)

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CIV - inconnue2

I do not know  the exact background of this Ivorian person. But his “Nigerian” score looks quite pronounced! Even when also one other Ivorian person in my survey group received a double digit score for socalled “Nigeria”. Unless other ancestral scenarios apply (such as recent Krio lineage) it might be best to simply regard it as a mislabeling of DNA which is also found among Ghanaians further east. Even Akan ones.

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BURKINA FASO (1/2 Mossi & 1/2 Tunisian)

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BF - Mossi plus tunisian

Although this person is actually mixed still very useful to see how “Ghanaian, Liberian & Sierra Leonean” is also covering DNA from Burkina Faso. To be more precise Gur-speaking origins as this person’s parent is Mossi. Scaled to 100% it is quite predominant: 41.6/48.9=85.1%! So it pays to be aware that country name labeling in DNA testing should never be taken too literally. Although it is of course quite indicative if you also take into account neighbouring countries! This person’s Tunisian half is also adequately described btw.

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Notes

1) Sometimes it almost seems that admixture analysis is being considered mere guessology by its fiercest critics. Or only fit for cocktail parties as the saying goes 😉 This has however not been my experience. I do agree that performance among the various DNA testing companies and third party websites is very variable. And obviously even more so going back in time. I have myself only tested with 23andme and Ancestry and I found that with correct interpretation and knowledge of their methodology you can indeed derive useful information from admixture/ethnicity results. Which were of course not just pulled out of a hat.

I strongly believe that when Tracing African Roots most people do not have the luxury to be snobbish about admixture analysis. Instead they will want to maximize informational value from any promising source available, despite shortcomings. Combining with other research findings (DNA matches, genealogy, relevant historical context, other types of DNA testing, etc.). in order to achieve complementarity rather than putting all your eggs in just one basket.

I know of many people who made important discoveries about their genetic ancestry by using their admixture results a.k.a. ethnicity estimates. For example I have heard several stories by West Indians who had unexpected Asian admixture, minor but still substantial (>10%). And this information was really useful to them as it lead them to previously unknown Asian contract labourer ancestors. There are plenty of other ancestral scenarios for Afro-Diasporans which can be illuminated by way of the continental breakdown which is usually quite accurate.

The regional or subcontinental percentages are indeed not to be taken all too literally. But again I know several persons who did rely on distinctive regional scores to make a breakthrough in their ancestral quest For example I have been told about at least three instances of NPE being confirmed whereby the father turned out to be East African instead of African American or West Indian. In one case indicated by the very predictive “East African” category on 23andme (pre-update) but also by a singular combination of “Southeastern Bantu” and “Middle Eastern” regional scores on AncestryDNA. Many times I have also seen how unexpected partial Cape Verdean lineage could quite reliably be corroborated by  “Senegal” scores on AncestryDNA. Not only for African Americans, but also for Hawaiians (due to whaling connections, see upcoming blog post)!

Such cases are bound to increase now that 23andme’s regional granularity has been significantly improved. All the more reason to resist being overly dismissive about admixture analysis, as this may deprive you of valuable insights! Although naturally this does not imply you should stop informing your self about any inherent limitations or imperfections. Reviewing the results of native Africans provides a good independent measure in my opinion to evaluate the usefulness of 23andme’s newly updated African breakdown. For more discussion see also:

2I have been gathering African testresults on 23andme for many years already. Originally to gain a greater understanding of the African categories included in 23andme’s old version of Ancestry Composition when it was being updated in 2012/2013. Thanks to the kind willingness of people to share their results I was able then to compile some sketchy “population averages” in 2013 which I shared on 23andme’s online community at that time. These survey findings can still be seen in this online spreadsheet. The individual results can be seen by clicking on the tabs on the bottom of the sheet. The screenshots of their results have also been featured on these blog pages:

In 2018 I blogged about the former Country of Ancestry results being reported for Africans on 23andme (in 2015):

3) Aside from Cape Verdeans my survey features several other people of mixed-race background. Usually 1 parent being from a specific African country and 1 parent being from Europe. But also Africans with 1 European great-grandparent. In order to make the African composition results inter-comparable between all my survey participants I have scaled the African part of 23andme’s breakdown to 100% for people of mixed background. Basically I applied the following formula:

  • Scaled amount = % for a given African region divided by % of total African amount (all based on group averages)

The scaling formula I used is very simple therefore and can be verified from within the spreadsheet by clicking on any cell featuring a regional score and then viewing the calculation in the function bar (fx) in the upper left corner. All other Excel formulas I used throughout the sheet and especially in the tab “Stats” can also be verified in this same way.

4) Among my Liberian and Sierra Leonean samples are also some people of Krio and Americo-Liberian descent. They showed the greatest degree of variation. Often also showcasing high “Nigerian” and even considerable  “Congolese” scores. In order to avoid any distortion Krio and Americo-Liberians are not included in the group averages I calculated in Table 1. Because after all these people’s genetics are (partially) deriving from Trans-Atlantic Slave Trade and therefore in a way more similar to Afro-Diasporans. However their individual breakdowns are very fascinating in themselves. And the contrast with “native” Liberian & Sierra Leonean results,  which are far more homogeneous is illuminating how 23andme’s update has made great strides! “Ghanaian, Liberian & Sierra Leonean” clearly being predominant for the latter.