posted
2004 by The American Society of Human Genetics. All rights reserved.
Ethiopian Mitochondrial DNA Heritage: Tracking Gene Flow Across and Around the Gate of Tears
Toomas Kivisild,1 Maere Reidla,1 Ene Metspalu,1 Alexandra Rosa,1 Antonio Brehm,2 Erwan Pennarun,1 Jüri Parik,1 Tarekegn Geberhiwot,3 Esien Usanga,4 and Richard Villems1 1Estonian Biocentre and Tartu University, Tartu, Estonia; 2Center of Macaronesian Studies, University of Madeira Penteada, Funchal, Portugal; 3Birmingham and Solihull Teaching Hospital, Birmingham, United Kingdom; and 4Department of Haematology, University of Calabar, Calabar, Nigeria Address for correspondence and reprints: Dr. Toomas Kivisild, Estonian Biocentre, Riia 23, Tartu 51010, Estonia. E-mail: tkivisil@ebc.ee
Abstract Approximately 10 miles separate the Horn of Africa from the Arabian Peninsula at Bab-el-Mandeb (the Gate of Tears). Both historic and archaeological evidence indicate tight cultural connections, over millennia, between these two regions. High-resolution phylogenetic analysis of 270 Ethiopian and 115 Yemeni mitochondrial DNAs was performed in a worldwide context, to explore gene flow across the Red and Arabian Seas. Nine distinct subclades, including three newly defined ones, were found to characterize entirely the variation of Ethiopian and Yemeni L3 lineages. Both Ethiopians and Yemenis contain an almost-equal proportion of Eurasian-specific M and N and African-specific lineages and therefore cluster together in a multidimensional scaling plot between Near Eastern and sub-Saharan African populations. Phylogeographic identification of potential founder haplotypes revealed that approximately one-half of haplogroup L0–L5 lineages in Yemenis have close or matching counterparts in southeastern Africans, compared with a minor share in Ethiopians. Newly defined clade L6, the most frequent haplogroup in Yemenis, showed no close matches among 3,000 African samples. These results highlight the complexity of Ethiopian and Yemeni genetic heritage and are consistent with the introduction of maternal lineages into the South Arabian gene pool from different source populations of East Africa. A high proportion of Ethiopian lineages, significantly more abundant in the northeast of that country, trace their western Eurasian origin in haplogroup N through assorted gene flow at different times and involving different source populations.
Summary conclusion:
In summation, Ethiopian and Yemeni maternal lineages can be seen as composites of both sub-Saharan and western Eurasian mtDNA haplogroups that coexist in almost equal proportions on both sides of the Red Sea. On the surface, it suggests a very extensive bidirectional gene flow between the two areas, readily supported by historic narratives as well as quantitative population statistics. Founder analysis of individual elements of this composition, however, revealed that, during the last several thousands of years, the populations of the Horn of Africa and southern Arabia, though sharing a minor part of their maternally inherited genomes, had received major demic influences from different sources—which they do not necessarily share—including the Near East, India, and northeastern and southeastern Africa. The presence of a frequent founder sequence type of an ancient and as-yet-uncharacterized haplogroup L6 in the Yemeni population, with no haplotype match in the African data base, intriguingly points to a possibly early gene flow across the Red Sea or to a signal of gene flow from an African population that has not yet been sampled.
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Comparison between Jewish populations and non-Jewish neighbors Haplogroup distributions and haplotype networks: Yemenite Jews and non-Jews
The mitochondrial haplogroup distributions of Yemenite Jews were compared to those of their non-Jewish neighbors (Fig. 2, Supporting Information Fig. S1). The frequency of sub-Saharan African L(xM,N) haplotypes is higher in the non-Jewish population (30%) than in the Jews (20%) (see Fig. 2). A previous study of 115 non-Jewish Yemeni found even higher levels of L(xM,N) haplotypes (48%, Kivisild et al., 2004) although those samples were collected in Kuwait, which likely produced an over-sampling of individuals of African ancestry as Yemeni living in Kuwait are predominantly Akhdam (a low status Yemeni population of African ancestry) or from Hadrawmat (a region known to have higher African ancestry (Cerny et al., 2008). We believe that our expansive sampling of Yemen provides a better representation of non-Jewish Yemeni genetic diversity than any previously collected sample and, thus, we focus subsequent analyses on our Yemeni samples. The diversity of L(xM,N) haplotypes is also reduced in the Yemenite Jewish population as compared with non-Jewish Yemeni, with a complete lack of deeper L0-L2 haplotypes that are common in the non-Jewish Yemeni population. A previous study of Yemenite Jews found a similar frequency of L(xM,N) (18%) and similar lack of L0-L2 haplotypes (Behar et al., 2008). Though reduced in comparison to Yemenis, the frequency and diversity of L(xM,N) haplotypes in Yemenite Jews is still much higher than typically seen in other Jewish populations.
The Yemenite Jewish population also contains a high frequency of west Eurasian haplogroups, including most of the major subclades of R (∼67%) as well as non-R haplogroups N and W (∼9%), in addition to haplogroup M (∼4%) that is found both in and out of Africa. Some of the Eurasian haplogroups in the Yemenite Jews are entirely absent in the non-Jewish Yemeni population, i.e. HV1, I1, J2a1a, U, U1 and W, suggesting some non-Yemeni Eurasian maternal contribution to the Jewish population. The R subclades, e.g., HV, J, U, are found at high frequencies further north in the Middle East/Caucasus region; e.g. Saudi Arabia (70.5%), Jordan (77%), Palestine (74%), Syria (87%), Bedouin (69%), Iraq (87%), and Iran (80%) (compiled in (Abu-Amero et al., 2007), indicating a potential source for R variation in the Yemenite Jews.
A network analysis was used to represent the exact sequence differences between haplotypes and illustrate the evolutionary relationship of Jewish and non-Jewish Yemeni (Supporting Information Fig. S1). The two populations are clearly different, as only two of the haplotypes in the Jewish population are identical to haplotypes in the non-Jewish population (2/30, 6.7%). On average, each Jewish individual's haplotype is ∼2.1 mutational steps away from a non-Jewish Yemeni haplotype, with a few individuals as many as four or six mutations away. When comparisons are made that include the larger Yemeni dataset (n = 115) collected by Kivisild et al. ( 2004) in Kuwait and the larger Yemenite Jewish sample (n = 119) collected by Behar et al. ( 2008), 19.3% (11/57) of Jewish haplotypes are identical to a haplotype in the non-Jewish population. Haplogroup distributions and haplotype networks: Ethiopian Jews and non-Jews
Next, Ethiopian Jewish individuals were compared with non-Jewish Semitic-speaking Ethiopians (Kivisild et al., 2004) (Fig. 2, Supporting Information Fig. S2). Examination of the haplogroup distribution reveals Ethiopian Jews to be a potential subset of the greater Ethiopian population (see Fig. 2). With one exception (L3b2), no unique haplogroup was identified in the Ethiopian Jewish population that was not also present in the non-Jewish population. The Ethiopian Jewish proportion of L(xM,N) haplotypes is nearly identical to that found in Semitic-speaking Ethiopians, i.e., just over 50% in both populations. Ethiopian Jewish and non-Jewish haplotypes show a great deal of overlap, with a high frequency of Jewish haplotypes found in the non-Jewish population (9/27, 33.3%). Furthermore, each Ethiopian Jewish haplotype is on average only 0.88 mutations away from a non-Jewish Ethiopian haplotype, suggesting a close and recent relationship between the two populations. In contrast, the Ethiopian Jewish population shows very low mitochondrial similarity to other Jewish populations, with no haplotypes identical to any found in other Jewish populations (Thomas et al., 2002; Behar et al., 2008).
Jewish Diaspora populations are some of the most studied populations in the world due to their successful migration and colonization of multiple global regions, their unique history of population isolation, and the wealth of archaeological, linguistic, and genetic data available. We focus on two Jewish groups at the geographic crossroads of some of the most significant migrations in human history, including the first migration of modern humans out of Africa. We compare mitochondrial diversity between these Jewish populations and surrounding groups in order to better understand their maternal population histories and the broader history of the region itself. We integrate our data with other anthropological data to investigate alternate origin and migration histories.
Our data show that Yemenite and Ethiopian Jewish populations differ from other Jewish Diaspora populations due to a high frequency of sub-Saharan African L(xM,N) mitochondrial haplotypes, i.e., ∼20% in Yemenite Jews and ∼50% in Ethiopian Jews. A higher frequency of L(xM,N) haplogroups could be explained by proximity to Africa except for the fact that all North African Jewish populations (n = 33 Moroccan, Tunisian, and Libyan) carry only a single L haplotype and other Middle Eastern Jewish populations (n = 23 Iranian and Iraqi) have no L haplotypes (Picornell et al., 2006). This high frequency of L(xM,N) haplogroups in both Yemenite and Ethiopian Jews suggests a relatively large number of African founders and/or a fair amount of admixture with African populations. A very high frequency of the Eurasian haplogroup R0a was also found in both Yemenite Jews (11%) and Ethiopian Jews (22%). However, despite the high frequency of L(xM,N) and R0a haplogroups in both Yemenite and Ethiopian Jewish populations, no exact haplotype matches were identified between the two Jewish populations. This low level of haplotype sharing implies very little gene flow between the two populations, despite their geographic proximity, and potentially unique population histories for each population.
Ethiopian Jewish population history
In contrast to Yemenite Jews, our analysis of Ethiopian Jewish mitochondrial diversity indicates strong similarity with the neighboring non-Jewish population, e.g. both populations carry ∼50% L(xM,N) haplotypes and 38% of the Jewish haplotypes have exact matches with non-Jewish Ethiopian haplotypes. Ethiopian Jewish mitochondrial diversity is, effectively, a subset of Ethiopian non-Jewish diversity. This result supports previous studies of Ethiopian Jewish mtDNA, which also show a high similarity between Ethiopian Jewish and non-Jewish sequences (Zoossmann-Diskin et al., 1991; Ritte et al., 1993; Thomas et al., 2002; Behar et al., 2008).
The main alternative origin theories for the Ethiopian Jewish population consist of (1) descent from ancient Israeli exiles ∼2,500–2,700 years ago, (2) descent from Ethiopian converts to Judaism in the fourth century, and (3) descent from Ethiopian Christians who adopted Jewish Biblical practices in 14th–16th centuries. The fact that Ethiopian Jewish mitochondrial diversity represents a subset of non-Jewish Ethiopian diversity suggests that the Jewish community may have formed from a local subsampling of the Ethiopian population. Additionally, the lack of shared haplotypes with other Jewish populations (Thomas et al., 2002; Behar et al., 2006) further weakens support for descent from ancient (female) Israeli exiles. Finally, the age of ∼1,000–2,160 years for the 16305(T) variant implies a minimal age for the Ethiopian Jewish population that is too recent to be consistent with the first theory.
The second and third origin theories both suggest that the Jewish population derived directly from converted Ethiopians, either from Agaw-speakers in the forth century CE or Ethiopian Orthodox Christians in the 14th–15th centuries CE. Our simulation analyses suggest that the number of converted female individuals, i.e., the founding maternal population, might have been as small as 224 effective individuals. The timeframes for both origin theories are within the range of our simulation estimates for the minimum age of the Jewish population, i.e. ∼420–1,690YBP (although the age estimated using the method of Tavare et al. ( 1997) is older than both origin theories). Linguistic and historic data support the idea that Judaism was present in Ethiopia prior to Ethiopian Orthodox Christianity, thus accounting for the similarity between the two religions, i.e., contra the third origin theory. Specifically, there are numerous Jewish-Aramaic or Hebrew loanwords for Jewish religious concepts (meswat [“commandment” or “charity”], tabot [“Noah's Ark” or “Ark of the Covenant], ta'ot [idol]) in the Ge'ez version of the Ethiopic Old Testament, attesting to a Jewish presence in Ethiopia at or prior to the time of the translation of the Christian Bible from Greek (Polotsky, 1964; Kaplan, 1992). Additionally, an historical account by Venetian explorer Marco Polo describes Jews in Abyssinia (Ethiopia) as far back as the 13th century CE (Quirin, 1992), thus supporting an early presence of Jews in Ethiopia. However, if the second origin theory is correct, Ethiopian Jews would have spoken Agaw dialects prior to the adoption of Amharic (Henze, 1977; Quirin, 1992; Kessler, 1996) leading to the prediction that Ethiopian Jews might be genetically closer to Cushitic-speakers than Semitic-speakers (Henze, 1977). This prediction is not supported by our data, i.e., there are fewer haplotypes in the Ethiopian Jewish population found in Cushitic Ethiopians than Semitic Ethiopians (15.4% vs 34.6%). Thus, our genetic data provide support for a theory of large-scale conversion of local Ethiopians, but cannot distinguish between the two primary conversion theories.
Maternal and paternal histories may vary for Ethiopian Jews as for Yemenite Jews. For instance, we assayed nine Y microsatellite markers in the male R0a1b individuals and found all males exhibited a different Y haplotype (data not shown), in contrast to their identical mitochondrial genomes. A previous study of Y variation showed a uniquely close relationship between Ethiopian Jews and Africans, similar to our mitochondrial data, but also demonstrated a high level of shared Jewish ancestry in Ethiopian Jews in contrast to our mitochondrial data (Shen et al., 2004). Shared paternal, but not maternal, Jewish ancestry would be consistent with the popular Ethiopian legend of the Queen of Sheba, in which Prince Menelik, the purported son of Israeli King Solomon and Ethiopian Queen of Sheba, may have introduced as many as 10,000 Israeli men into the local Ethiopian population, converting many Ethiopian women to the Jewish religion (Quirin, 1992).
Our mitochondrial DNA study of Jewish populations in the HOA and Arabia sheds light on the history of two religiously defined groups formed relatively recently in these geographic regions. We found no identical haplotypes shared between Yemenite and Ethiopian Jewish populations despite their geographic proximity. Our data on Yemenite Jews suggest possible maternal descent from ancient Israeli exiles, and also demonstrate shared African and Middle Eastern ancestry with little evidence for large-scale conversion of local Yemeni. In contrast, our data on Ethiopian Jews suggest maternal descent primarily from the local Ethiopian population.
posted
One problem I have the article is that it claims the N clades present in Africa and Yemen are of Eurasian origins. Yet the type present in Africa--N1-- is only found in Africa, and N1a which is common in East Africa and nearby Yemen is found in very low frequencies anywhere else in Eurasia.
This is why I agree with Kivisild et al. that N1 like M1 should not be attributed to Eurasian origins.
Posts: 26239 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: One problem I have the article is that it claims the N clades present in Africa and Yemen are of Eurasian origins. Yet the type present in Africa--N1-- is only found in Africa, and N1a which is common in East Africa and nearby Yemen is found in very low frequencies anywhere else in Eurasia.
Exactly. One of my problems with it as well; still, I think it is an OK article.
quote:This is why I agree with Kivisild et al. that N1 like M1 should not be attributed to Eurasian origins.
Kivislid et al., said the exact opposite actually:
quote:Kivislid et al., 2004 said: Both Ethiopians and Yemenis contain an almost-equal proportion of Eurasian-specific M and N and African-specific lineages and therefore cluster together in a multidimensional scaling plot between Near Eastern and sub-Saharan African populations.
^Which was later refuted by Tishkoff et al., (2006):
quote:Studies of human mtDNA genomes demonstrate that the root of the human phylogenetic tree occurs in Africa. Although two mtDNA lineages with an African origin (haplogroups M and N) were the progenitors of all non-African haplogroups, macrohaplogroup L (including haplogroups L0-L6) is limited to sub-Saharan Africa. Several L haplogroup lineages occur most frequently in eastern Africa (e.g., L0a, L0f, L5, L3g), but some are specific to certain ethnic groups, such as haplogroup lineages L0d and L0k that previously have been found nearly exclusively among southern African “click” speakers. Few studies have included multiple mtDNA genome samples belonging to haplogroups that occur in eastern and southern Africa but are rare or absent elsewhere. This lack of sampling in eastern Africa makes it difficult to infer relationships among mtDNA haplogroups or to examine events that occurred early in human history.
quote:Originally posted by Calabooz: Kivislid et al., said the exact opposite actually:
Well not anymore since I recall recent papers admitting African origins, or perhaps I confused him with someone else.
Posts: 26239 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: One problem I have the article is that it claims the N clades present in Africa and Yemen are of Eurasian origins. Yet the type present in Africa--N1-- is only found in Africa, and N1a which is common in East Africa and nearby Yemen is found in very low frequencies anywhere else in Eurasia.
Exactly. One of my problems with it as well; still, I think it is an OK article.
quote:This is why I agree with Kivisild et al. that N1 like M1 should not be attributed to Eurasian origins.
Kivislid et al., said the exact opposite actually:
quote:Kivislid et al., 2004 said: Both Ethiopians and Yemenis contain an almost-equal proportion of Eurasian-specific M and N and African-specific lineages and therefore cluster together in a multidimensional scaling plot between Near Eastern and sub-Saharan African populations.
^Which was later refuted by Tishkoff et al., (2006):
quote:Studies of human mtDNA genomes demonstrate that the root of the human phylogenetic tree occurs in Africa. Although two mtDNA lineages with an African origin (haplogroups M and N) were the progenitors of all non-African haplogroups, macrohaplogroup L (including haplogroups L0-L6) is limited to sub-Saharan Africa. Several L haplogroup lineages occur most frequently in eastern Africa (e.g., L0a, L0f, L5, L3g), but some are specific to certain ethnic groups, such as haplogroup lineages L0d and L0k that previously have been found nearly exclusively among southern African “click” speakers. Few studies have included multiple mtDNA genome samples belonging to haplogroups that occur in eastern and southern Africa but are rare or absent elsewhere. This lack of sampling in eastern Africa makes it difficult to infer relationships among mtDNA haplogroups or to examine events that occurred early in human history.
What's your take on Ethiopian Jews carrying ROa at 22%?
It could be geographical with Jews being more Northern. R0a, formerlly "Pre-HV" is found in the whole horn of Africa. I think about 10% all sampled pooled together. When looking at the mtdna phylogenetic tree :
Its easy to see why lineages springing from L3* that left the Horn: M and N have some of their closest subclades found on both sides of the red sea, RO, N1, M1, X, U6.
Posts: 2463 | From: New Jersey USA | Registered: Dec 2007
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quote:Genetic Evidence for Complexity in Ethnic Differentiation and History in East Africa Estella S. Poloni1∗ ,#, Yamama Naciri2#, Rute Bucho1,2, Re´gine Niba2, Barbara Kervaire3, Laurent Excoffier4,5, Andre´ Langaney1,6 and Alicia Sanchez-Mazas1 1Laboratoire d’Anthropologie, Ge´ne´tique et Peuplements, De´partement d’Anthropologie et d’E´ cologie, Universite´ de Gene`ve, 1211 Geneva 4, Switzerland 2Laboratoire de Syst´ematique V´eg´etale et Biodiversit´e, Unit´e de Phylog´enie et G´en´etique Mol´eculaires, Conservatoire et Jardin botaniques, 1292 Chamb´esy, Geneva, Switzerland 3Unit´e d’Immunologie de la Transplantation, Laboratoire National de R´ef´erence pour l’Histocompatibilit´e, Hˆopitaux Universitaires de Gen`eve, 1200 Geneva, Switzerland 4Computational and Molecular Population Genetics Laboratory, Institute of Ecology and Evolution, Universit¨at Bern, 3012 Bern, Switzerland 5Swiss Institute of Bioinformatics, http://www.isb-sib.ch/ 6Mus´eum National d’Histoire Naturelle, 75281 Paris Cedex 05, France
Summary The Afro-Asiatic and Nilo-Saharan language families come into contact in Western Ethiopia. Ethnic diversity is particularly high in the South, where the Nilo-Saharan Nyangatom and the Afro-Asiatic Daasanach dwell. Despite their linguistic differentiation, both populations rely on a similar agripastoralist mode of subsistence. Analysis of mitochondrial DNA extracted from Nyangatom and Daasanach archival sera revealed high levels of diversity, with most sequences belonging to the L haplogroups, the basal branches of the mitochondrial phylogeny. However, in sharp contrast with other Ethiopian populations, only 5% of the Nyangatom and Daasanach sequences belong to haplogroups M and N. The Nyangatom and Daasanach were found to be significantly differentiated, while each of them displays close affinities with some Tanzanian populations. The strong genetic structure found over East Africa was neither associated with geography nor with language, a result confirmed by the analysis of 6711 HVS-I sequences of 136 populations mainly from Africa. Processes of migration, language shift and group absorption are documented by linguists and ethnographers for the Nyangatom and Daasanach, thus pointing to the probably transient and plastic nature of these ethnic groups. These processes, associated with periods of isolation, could explain the high diversity and strong genetic structure found in East Africa.
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I also thought that the following study was of particular interest:
Note: Ethiopian origin for M1 indicated
Source: Mitochondrial DNA geneflow indicates preferred usage of the Levant Corridor over the Horn of Africa passageway D. J. Rowold Æ J. R. Luis Æ M. C. Terreros Æ Rene J. Herrera (2007)
Haven't finished reading this yet, just thought that particular image was telling. I'll Comment more if anything interesting pops up
Posts: 1502 | From: Dies Irae | Registered: Oct 2010
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quote:Correspondence analysis A correspondence analysis including the ten study collections and the 15 additional African or Eurasian populations is shown in online Fig. 1 at http://www.fiu.edu/~herrerar. Axes 1 and 2 account for 34.8% of the total inertia (20.7 and 13.2%, respectively). The two-dimensional pattern displays four distinct clusters: the sub-Saharan Africans located in the most positive portion of axis 1 (a); the Indian– Pakistani populations partitioned in the upper-left quadrant (b) and the three Ethiopian populations (Amhara, Cushitic and Tigrai) sandwiched between the sub-Saharan cluster and the North African and Middle East populations (c), and a diffuse assembly of the North African and Middle East collections in the bottom-left quadrant (d). These fit well within the phylogeographical patterns established by previous genetic research (Cavalli-Sforza et al. 1994; Underhill et al. 2000; Salas et al. 2002; Kivisild et al. 2004). This corroboration suggests representative population sampling.
PS: See the download link I provided
Posts: 1502 | From: Dies Irae | Registered: Oct 2010
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Y-chromosomal SNPs are used in phylogenetical studies because in a paternal lineage the Y-SNP “set” is only changed by mutational events. Lower migration rates of males in the past in local scale cause different haplogroup distributions in closed populations. In the actual haplogroup tree (ISOGG 2008) 20 main haplogroups (A-T) are listed.
The Y-chromosomes of 173 unrelated males from Ethiopia (most of them contain to the Amharics) were analysed. For typing, a set of 40 SNPs, which include most of the main haplogroups of the actual phylogenetical tree, were used in combination with the Multiplex PCR Kit (Qiagen) and the SNaPshot™ Multiplex Kit (Applied Biosystems). The ABI PRISM™ 310 Genetic Sequenzer was used for allele calling.
The distribution of the five detected main haplogroups was calculated against the total number of the 173 analysed samples. 40 males (23.1% of analysed samples) belong to the haplogroup A*. 88 samples (50.9%) were related to haplogroup E*, 43 (24.9%) to haplogroup J* and one sample (0.6%) to each haplogroup F* and G*.
Source: Distribution of Y-chromosomal SNP-haplogroups between males from Ethiopia
M. Kohla, R. Lessiga, J. Edelmanna, J. Dresslera and K. ThieleCorresponding Author Contact Information, a, E-mail The Corresponding Author (2009)
From the 173 analysed males, also for 173 a classification could be made. Distributions between other 173 males were: 40 males (23.1% of analysed samples) belong to the haplogroup A*, 88 males (50.9%) were related to haplogroup E*, 43 (24.9%) to haplogroup J* and one male (0.6%) to each haplogroup F* and G*. For haplogroup E* a more detailed distribution was possible. 5 males belong to haplogroup E*, 19 to haplogroup E1b1*, 43 to haplogroup E1b1b1*, 19 to haploproup E1b1b1c* and 2 to haplogroup E2.
From the 20 main haplogroups in the Y-chromosomal haplogroup tree, only 5 were detected in the analysed Amharic population in Ethiopia. Haplogroup A is near the roots of the tree and is only found among males on the African continent. The major haplogroup detected was E. Haplogroup E has its origin in West Africa. Due to immigration haplogroup A, which originally dominated in Ethiopia, has been partly replaced.
What do they mean when they say E has it's origin in west Africa? Anybody have any clue?
Posts: 1502 | From: Dies Irae | Registered: Oct 2010
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quote:Originally posted by the lioness: 2004 by The American Society of Human Genetics. All rights reserved.
Ethiopian Mitochondrial DNA Heritage: Tracking Gene Flow Across and Around the Gate of Tears
Toomas Kivisild,1 Maere Reidla,1 Ene Metspalu,1 Alexandra Rosa,1 Antonio Brehm,2 Erwan Pennarun,1 Jüri Parik,1 Tarekegn Geberhiwot,3 Esien Usanga,4 and Richard Villems1 1Estonian Biocentre and Tartu University, Tartu, Estonia; 2Center of Macaronesian Studies, University of Madeira Penteada, Funchal, Portugal; 3Birmingham and Solihull Teaching Hospital, Birmingham, United Kingdom; and 4Department of Haematology, University of Calabar, Calabar, Nigeria Address for correspondence and reprints: Dr. Toomas Kivisild, Estonian Biocentre, Riia 23, Tartu 51010, Estonia. E-mail: tkivisil@ebc.ee
Abstract Approximately 10 miles separate the Horn of Africa from the Arabian Peninsula at Bab-el-Mandeb (the Gate of Tears). Both historic and archaeological evidence indicate tight cultural connections, over millennia, between these two regions. High-resolution phylogenetic analysis of 270 Ethiopian and 115 Yemeni mitochondrial DNAs was performed in a worldwide context, to explore gene flow across the Red and Arabian Seas. Nine distinct subclades, including three newly defined ones, were found to characterize entirely the variation of Ethiopian and Yemeni L3 lineages. Both Ethiopians and Yemenis contain an almost-equal proportion of Eurasian-specific M and N and African-specific lineages and therefore cluster together in a multidimensional scaling plot between Near Eastern and sub-Saharan African populations. Phylogeographic identification of potential founder haplotypes revealed that approximately one-half of haplogroup L0–L5 lineages in Yemenis have close or matching counterparts in southeastern Africans, compared with a minor share in Ethiopians. Newly defined clade L6, the most frequent haplogroup in Yemenis, showed no close matches among 3,000 African samples. These results highlight the complexity of Ethiopian and Yemeni genetic heritage and are consistent with the introduction of maternal lineages into the South Arabian gene pool from different source populations of East Africa. A high proportion of Ethiopian lineages, significantly more abundant in the northeast of that country, trace their western Eurasian origin in haplogroup N through assorted gene flow at different times and involving different source populations.
Summary conclusion:
In summation, Ethiopian and Yemeni maternal lineages can be seen as composites of both sub-Saharan and western Eurasian mtDNA haplogroups that coexist in almost equal proportions on both sides of the Red Sea. On the surface, it suggests a very extensive bidirectional gene flow between the two areas, readily supported by historic narratives as well as quantitative population statistics. Founder analysis of individual elements of this composition, however, revealed that, during the last several thousands of years, the populations of the Horn of Africa and southern Arabia, though sharing a minor part of their maternally inherited genomes, had received major demic influences from different sources—which they do not necessarily share—including the Near East, India, and northeastern and southeastern Africa. The presence of a frequent founder sequence type of an ancient and as-yet-uncharacterized haplogroup L6 in the Yemeni population, with no haplotype match in the African data base, intriguingly points to a possibly early gene flow across the Red Sea or to a signal of gene flow from an African population that has not yet been sampled.
Good article,
Basically, it means that people on both sides of the Red Sea are related to each other, but with some infusion from their respective spheres. Simple and Sweet, but unlikley to be accepted by the Afro Crowds, where the facts do not fit their Agenda!Posts: 422 | From: Leave No Stone Unturned! | Registered: Feb 2011
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Add that to all of the other Y chromosomal and mtDNA studies published within the last three years instead of looking at Lioness's 2004 study
What do you mean "unlikely to be accepted by afro-crowds"?? It is the exact opposite, YOU refused to acknowledge the more RECENT articles provided herein
-------------------- L Writes: Posts: 1502 | From: Dies Irae | Registered: Oct 2010
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posted
I am done with the other because i was correct,but now here something i was reading recently in another forum.
Please read all of it,because it has good info,
I added some info because the chat was good. Make sure you check out the chick below. More of my comments are below. Please read all of it,because it has good info, Thanks.
I found this and just reading some of it and just sharing the info. Read some of the chat. Why Do Nigerians Think Ethiopians And Somalis Are Mixed? - Ethnic, Racial, Or Sectarian Politics - Nairaland Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Wazimu: 4:11pm On Aug 23, 2010 This is not true people. They are NOT mixed! East Africans from the Horn are genetically just as African as any Nigerian. I don't know why many Nigerians and others make this assumption. Africa is a diverse place and we shouldn't think all Africans look the same.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Ikengawo: 4:40pm On Aug 23, 2010 its a silly thing to think being that the black race was the first race. ethiopians and somalians didn't come from arabs, its the other way around.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Wazimu: 5:05pm On Aug 23, 2010 Yes Indeed
I read some genetic studies on Ethiopians and Somalis they are essentially completely African with little to no Arabian blood. Arabians on the other hand have TONS of African blood.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Inked_Nerd(f): 9:33am On Aug 24, 2010 Its because they are still suffering from post slavery/colonialist ideology. Some still think that you need a drop of "white blood" in order to "look Somalian/Ethiopian". There are people in Ethiopia that look just like Nigerians.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by tpiah: 2:22pm On Aug 24, 2010 Since they're closer to the arab countries, chances are they might have been mixed at some point in time.
after all, according to tradition, queen sheba had a child with king solomon.
that legend [whether true or not] indicates interracial mixing wasnt unheard of.
btw, there are other tribes in ethiopia besides the amhara. Some ethiopians are plain black.
Since they're closer to the arab countries, chances are they might have been mixed at some point in time.
after all, according to tradition, queen sheba had a child with king solomon.
that legend [whether true or not] indicates interracial mixing wasnt unheard of.
btw, there are other tribes in ethiopia besides the amhara. Some ethiopians are plain black.
2010
Wazimu:
^ALL and yes I mean ALL Ethiopians are 'plain black'. It is all in your mind, these people are 100% African genetically, very little blood from Arabs.
I am an Amhara Ethiopian myself and noticed many Nigerians think this way.
I agree, it is all in their heads.
Wazimu:
^ALL and yes I mean ALL Ethiopians are 'plain black'. It is all in your mind, these people are 100% African genetically, very little blood from Arabs.
I am an Amhara Ethiopian myself and noticed many Nigerians think this way.
dont you mean many ethiopians think this way, mr or mrs four posts who just happened to chance on this thread this very day.
is there a particular reason you want to start attacking nigerians when some of your fellow amharas say the same?
some ethiopians are pure black with typical negro features, while others have the semitic faces commonly found around the horn of africa.
if you're dating a nigerian, that's no reason to butt into things, thank you.
so the queen of sheba is the lone example in the whole history of ethiopia, of interracial mixing, abi.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Wazimu: 10:25pm On Aug 24, 2010 the ones who look like semitic people are also pure africans (proven by modern science)
semitic people came from ethiopians, that is why some look like us. if an ethiopian looks like an arab it doesn't mean he is mixed, just evolution.
get it?
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Asari1986: 11:13pm On Aug 24, 2010
Ethiopians and Somalis have different look, (beautiful) but that does not mean they are MIXED. Its just the AFRICAN WAY. Its diverse and beautiful. You will see Ethios & Somalis with long soft hair, but you'll also see some that have very thick short hair. ITS THE AFRICAN WAY. LOVE IT
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by tpiah: 6:13pm On Aug 26, 2010 ^^if you cant have a simple discussion without resorting to insults, then you are very silly.
mind yourself o angry
explain these photos since you're so smart:
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Asari1986: 8:35pm On Aug 26, 2010
Well obviously these ones ARE mixed but I think what he is trying to say is MAJORITY of them (as a country) are not mixed. Weird, one looks totally ASAIN while the other two look WHITE, they don't look they are mixed with african.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Beaf: 4:12am On Aug 27, 2010
Wazimu, welcome to the forum. Unfortunately, your first post is a section created for the hardest nuts. You would have had a much better reception in the culture or politics sections.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by morpheus24: 6:47am On Aug 28, 2010
Wazimu:
This is not true people. They are NOT mixed! East Africans from the Horn are genetically just as African as any Nigerian. I don't know why many Nigerians and others make this assumption. Africa is a diverse place and we shouldn't think all Africans look the same.
Wazimu. This topic has been exhausted several times on this forum. You need only search key words. I would say you are correct in your above statment by claiming ethiopians as 100% African. They are. However it depends on the context as well i.e in terms of Genetics, history or culture. Amhara and tigre's share common ancient ancestors with groups in Yemen today.This however does not designate a mixed status to Ethiopians only that you share similar GENETIC markers with Yemenis. Oromos are less likely to carry these markers though
It should be noted that ancient Yemenis are said to have originated from East Africa in the first place with waves of new groups forming bottle neck communites that established specific phenotypical traits that have moved back and forth through that region. Therefore it should not be a shock to some that both groups share Genotypical as well as phenotypical traits. The Haplogroup that ties West Africans to East Africans is under the PN2 clade marker with a majority East Africans carrying the E3b or E3b1b1 version while the West African carrying the E3a marker. In other words there was a split with the founding groups but all originating from the same source onthe paternal side. In this context Ethiopians can claim their Africanes without a doubt, they are brown to black skin much like everyother set of Africans and limb porportins are consistent with Arid region dwellers of African entract.
Tpia still subscribes to black people with the so called " negro "affiliations and tends to veiw topics in terms of who is dating a Nigerina man. Go figurehuh?
________ tpiah:
Go ahead and explain the photos _________________
The pics you posted are an attempt at picture spamming. You have provided no specific evidence of the possible genetic lineages of the implied ethiopian/east African parents of the individuals you posted. This therefore cannot lend credence to your ascertion thata majority of Ethiopians are of mixed heritage.
What one can deduce from the pics is that there are Ethiopians who are of mixed heritage such as there are Nigerians, senegales or sierra leonians of such heritage as well and the further down the indices on a gradial line depending on what start to end point (i.e from black to white or white to black) the more the individual will appear to resemble the ethnic group it is bottlenecked into. The pics cannot be used as a general statement as regards the entire populatonn of Ethiopians based on observed phenotypical evidence.
Case in point , if your ascertion is true then AA's should not be regarded as Black people simply becaus they carry about a10-15% European genetic markers. To illustrate below pic of Ryan giggs cannot be used as a general statment to imply the genetic heritage of sierra leonians of mixed heritage even though Paternally Mr giigs is of African heritage on his Fathers side.
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by Wazimu: 10:49pm On Aug 28, 2010 It is because white people came from us, we are the closest to them from all SubSaharan Africans. The out of Africa migrations (all humans came from Africa) happened on the red sea coast in present day Eritrea or Djibouti. Linking us to them, not through admixture. There is very little non-African blood in Ethiopians.
You Nigerians also came from us Ethiopians.
We are the center of humanity
Re: Why Do Nigerians Think Ethiopians And Somalis Are Mixed? by morpheus24: 11:05pm On Aug 28, 2010 I will agree with the above bolded part as this is a possibility as to why such Children phenotypically would look more of the opposites ethnic group. however this is not the norm in many cases so the looks of the pics Tpiah posted are not typical of Ethiopians merged with Middle Easterners, Europeans or Asians.
As to your statments concerning Nigerians. This is incorrect. West aFricans and East Africans as stated earlier share a common founding father Ancestor. The two groups deviated to form clusters of genotype and phenotype. the clusters in ancient E africans carry through to other world populations while the ones that remained in Afircan interior remain the most genetically diverse of anywhere on the planet
So my dear it is actually the other way round. East Africans are an extract of the African supra genotype which interior Afircans carry the oldests hard codes in them.Case in pint there are West Africans who look phenotypically similar to East Africnas with the hard coded E3a founder genotype but nt vice versa for E3b/eb1b1i.e there is more diversity within African than outside of it ________________ My comment Well SOME AA HAVE EUROPEAN IN DNA,AND SOME DO NOT.
I did not read the rest of the chat Anyway for more of the chat click link.
posted
This is about the Somalis. Anywbody has a view about the below info?
Genetics Genetic genealogy, although a new tool that uses the genes of modern populations to trace their ethnic and geographic origins, has also helped pinpoint the possible background of the modern Somalis. Y DNA According to Y chromosome studies by Sanchez et al. (2005) and Cruciani et al. (2004), the Somalis are paternally closely related to certain Ethiopian groups, particularly Cushitic speakers:
"The data suggest that the male Somali population is a branch of the East African population − closely related to the Oromos in Ethiopia and North Kenya − with predominant E3b1 [now "E1b1b1"] cluster lineages... and that the Somali male population has approximately 15% Y chromosomes from Eurasia and approximately 5% from sub-Saharan Africa."
Besides comprising the majority of the Y DNA in Somalis, the E1b1b1a (formerly E3b1a) haplogroup also makes up a significant proportion of the paternal DNA of Ethiopians, Sudanese, Egyptians, Berbers, North African Arabs, as well as many Mediterranean and Balkan Europeans. The M78 subclade of E1b1b is found in about 77% of Somali males, which, according to Cruciani et al. (2007), may represent the traces of an ancient migration into the Horn of Africa from Egypt/Libya. After haplogroup E1b1b, the second most frequently occurring Y DNA haplogroup among Somalis is the Eurasian haplogroup T (M70), which is found in slightly more than 10% of Somali males. Haplogroup T, like haplogroup E1b1b, is also typically found among populations of Northeast Africa, North Africa, the Near East and the Mediterranean.
mtDNA According to mtDNA studies by Holden (2005) and Richards et al. (2006), a significant proportion of the maternal lineages of Somalis consists of the M1 haplogroup, which is common among Ethiopians and North Africans, particularly Egyptians and Algerians. M1 is believed to have originated in Asia, where its parent M clade represents the majority of mtDNA lineages (particularly in India). This haplogroup is also thought to possibly correlate with the Afro-Asiatic language family:
"We analysed mtDNA variation in ~250 persons from Libya, Somalia, and Congo/Zambia, as representatives of the three regions of interest. Our initial results indicate a sharp cline in M1 frequencies that generally does not extend into sub-Saharan Africa. While our North and especially East African samples contained frequencies of M1 over 20%, our sub-Saharan samples consisted almost entirely of the L1 or L2 haplogroups only. In addition, there existed a significant amount of homogeneity within the M1 haplogroup. This sharp cline indicates a history of little admixture between these regions. This could imply a more recent ancestry for M1 in Africa, as older lineages are more diverse and widespread by nature, and may be an indication of a back-migration into Africa from the Middle East."
Another mtDNA study indicates that:
"Somali, as a representative East African population, seem to have experienced a detectable amount of Caucasoid maternal influence... the proportion m of Caucasoid lineages in the Somali is m = 0.46 [46%]... Our results agree with the hypothesis of a maternal influence of Caucasoid lineages in East Africa, although its contribution seems to be higher than previously reported in mtDNA studies."
Overall, these genetic studies conclude that Somalis and their fellow Ethiopian and Eritrean Northeast African populations represent a unique and distinct biological group on the continent:
"The most distinct separation is between African and non-African populations. The northeastern-African -- that is, the Ethiopian and Somali -- populations are located centrally between sub-Saharan African and non-African populations... The fact that the Ethiopians and Somalis have a subset of the sub-Saharan African haplotype diversity -- and that the non-African populations have a subset of the diversity present in Ethiopians and Somalis -- makes simple-admixture models less likely; rather, these observations support the hypothesis proposed by other nuclear-genetic studies (Tishkoff et al. 1996a, 1998a, 1998b; Kidd et al. 1998) -- that populations in northeastern Africa may have diverged from those in the rest of sub-Saharan Africa early in the history of modern African populations and that a subset of this northeastern-African population migrated out of Africa and populated the rest of the globe. These conclusions are supported by recent mtDNA analysis (Quintana-Murci et al. 1999)."
HLA antigens
The analysis of HLA antigens has also helped clarify the possible background of the Somali people, as the distribution of haplotype frequencies vary among population groups.[81] According to Mohamoud et al. (2006):
"HLA antigens of the Somali population are not categorised as well as those of other international ethnic groups. We analysed the HLA antigens of 76 unrelated Somalis who lived in the west of England. HLA -A, -B, -C and DRB1 typing was performed by polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP) at a low-intermediate resolution level. Phenotype frequency, gene frequency and haplotype frequency were used to study the relationship between Somalis and other relevant populations. The antigens with highest frequencies were HLA -A1, A2, and A30; B7, B51 and B39; Cw7, Cw16, Cw17, Cw15 and Cw18; DR 13, DR17, DR8 and DR1. HLA haplotypes with high significance and characteristics of the Somali population are B7-Cw7, B39-Cw12, B51-Cw16, B57-Cw18. The result of HLA class I and class II antigen frequencies show that the Somali population appear more similar to Arab or Caucasoid than to African populations. The results are consistent with hypothesis, supported by cultural and historical evidence, of common origin of the Somali population."
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Here is the ethiopians. Genetic studies Wilson et al. (2001), an autosomal DNA study based on cluster analysis that looked at a combined sample of Amhara and Oromo, found that 62% of Ethiopeans fall into the same cluster of Ashkenazi Jews, Norwegians and Armenians. Only 24% of Ethiopians cluster with Bantus and Afro-Caribbeans, 8% with Papua New Guineans, and 6% with Chinese.
Tishkoff et al. (2009) identified fourteen ancestral population clusters which correlate with self-described ethnicity and shared cultural and/or linguistic properties in Africa in what was the largest autosomal study of the continent to date. The Burji, Konso and Beta Israel were sampled from Ethiopia. The Afroasiatic speaking Ethiopians sampled were cumulatively (Fig.5B) found to belong to: 71% in the "Cushitic" cluster, 6% in the "Saharan/Dogon" cluster, 5% in the "Niger Kordofanian" cluster, 3% each in the "Nilo-Saharan" and "Chadic Saharan" cluster, while the balance (12%) of their assignment was distributed among the remnant Associated Ancestral Clusters (AAC's) found in Sub-Saharan Africa. The "Cushitic" cluster was also deemed "closest to the non-African AACs, consistent with an East African migration of modern humans out of Africa or a back-migration of non-Africans into Saharan and Eastern Africa."
Paternal Lineages A composite look at most YDNA studies done so far reveals that,out of a total of 459 males sampled from Ethiopia, approximately 58% of Y-chromosome haplotypes were found to belong to Haplogroup E, of which 71% (41% of total) were characterized by one of its further downstream sub lineage known as E1b1b, while the remainder were mostly characterized by Haplogroup E1b1(x E1b1b,E1b1a), and to a lesser extent Haplogroup E2. With respect to E1b1b, some studies have found that it exists at its highest level among the Oromo, where it represented 62.8% of the haplotypes, while it was found at 35.4% among the Amhara, other studies however have found an almost equal representation of Haplogroup E1b1b at approximately 57% in both the Oromo and the Amhara. The haplogroup (as its predecessor E1b1) is thought to have originated in Ethiopia or elsewhere in the Horn of Africa. About one half of E1b1b found in Ethiopia is further characterized by E1b1b1a (M78), which arose later in north-eastern Africa and then back-migrated to eastern Africa.
Haplogroup J has been found at a frequency of approximately 18% in Ethiopians, with a higher prevalence among the Amhara, where it has been found to exist at levels as high as 35%, of which about 94% (17% of total) is of the type J1, while 6% (1% of total) is of J2 type. On the other hand, 26% of the individuals sampled in the Arsi control portion of Moran et al. (2004) were found to belong to Haplogroup J.
Another fairly prevalent lineage in Ethiopia belongs to Haplogroup A, occurring at a frequency of about 17% within Ethiopia, it is almost all characterized by its downstream sub lineage of A3b2 (M13). Restricted to Africa, and mostly found along the Rift Valley from Ethiopia to Cape Town, Haplogroup A represents the deepest branch in the Human Y- Chromosome phylogeny.
Finally, Haplogroup T at approximately 4% and Haplogroup B at approximately 3%, make up the remainder of the Y-DNA Haplogroups found within Ethiopia. The maternal ancestry of Ethiopians is similarly diverse. About half (52.2%) of Ethiopians belongs to mtdna Haplogroups L0, L1, L2, L3, L4, L5, or L6. These haplogroups are generally confined to the African continent. They also originated either in Ethiopia or very near. The other portion of the population belong to Haplogroup N (31%) and Haplogroup M1 (17%). There is controversy surrounding their origins as either native or a possible ancient back migration into Ethiopia from Asia.
The maternal ancestry of Ethiopians is similarly diverse. About half (52.2%) of Ethiopians belongs to mtdna Haplogroups L0, L1, L2, L3, L4, L5, or L6. These haplogroups are generally confined to the African continent. They also originated either in Ethiopia or very near. The other portion of the population belong to Haplogroup N (31%) and Haplogroup M1 (17%). There is controversy surrounding their origins as either native or a possible ancient back migration into Ethiopia from Asia.
Caucasoid gene flow into the Ethiopian gene pool occurred predominantly through males. Conversely, the Niger–Congo contribution to the Ethiopian population occurred mainly through females.
While there is debate among the scientific community of what exactly constitutes "Caucasoid gene flow", the same study further stated:
Indeed, Ethiopians do not seem to result only from a simple combination of proto-Niger–Congo and Middle Eastern genes. Their African component cannot be completely explained by that of present-day Niger–Congo speakers, and it is quite different from that of the Khoisan. Thus, a portion of the current Ethiopian gene pool may be the product of in situ differentiation from an ancestral gene pool."
Scott et al. (2005) similarly observed that the Ethiopian population is almost equally divided between individuals that carry Eurasian maternal lineages, and those that belong to African clades. They describe the presence of Eurasian clades in the country as sequences that "are thought to be found in high numbers in Ethiopia either as a result of substantial gene flow into Ethiopia from Eurasia (Chen et al., 2000; Richards et al., 2003), or as a result of having undergone several branching events in demic diffusion, acting as founder lineages for non-African populations". The researchers further found no association between regional origin of subjects or language family (Semitic/Cushitic) and their mitochondrial type:
The haplogroup distribution amongst all subjects (athletes and controls) from different geographical regions of Ethiopia is displayed in Table 3. As can be seen graphically in Fig. 3, the mtDNA haplogroup distribution of each region is similar, with all regions displaying similar proportions of African 'L' haplogroups (Addis Ababa: 59%, Arsi: 50%, Shewa: 44%, Other: 57%). No association was found between regional origin of subjects and their mitochondrial type (v2=8.5, 15 df, P=0.9). Similarly, the mtDNA haplogroup distribution of subjects (athletes and controls) speaking languages from each family is shown in Table 3. Again there was no association between language family and mitochondrial type (v2=5.4, 5 df, P=0.37). As can be seen in Fig. 4, the haplogroup distributions of each language family are again very similar.
In addition, Musilová et al. (2011) observed significant maternal ties between its Ethiopian and other Horn African samples with its Western Asian samples; particularly in terms of the HV1b mtDNA haplogroup. The authors noted:
"Detailed phylogeography of HV1 sequences shows that more recent demographic upheavals likely contributed to their spread from West Arabia to East Africa, a finding concordant with archaeological records suggesting intensive maritime trade in the Red Sea from the sixth millennium BC onwards."
According to Černý et al. (2008), many Ethiopians also share specific maternal lineages with areas in Yemen and other parts of Northeast Africa. The authors indicate that:
"The most frequent haplotype in west coastal Yemen is 16126–16362, which is found not only in the Ethiopian highlands but also in Somalia, lower Egypt and at especially high frequency in the Nubians. The Tihama share some West Eurasian haplotypes with Africans, eg J and K with Ethiopians, Somali and Egyptians."
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