Mitochondrial haplogroup H1 in north Africa: an early holocene arrival from Iberia

The Tuareg of the Fezzan region (Libya) are characterized by an extremely high frequency (61%) of haplogroup H1, a mitochondrial DNA (mtDNA) haplogroup that is common in all Western European populations. To define how and when H1 spread from Europe to North Africa up to the Central Sahara, in Fezzan, we investigated the complete mitochondrial genomes of eleven Libyan Tuareg belonging to H1. Coalescence time estimates suggest an arrival of the European H1 mtDNAs at about 8,000-9,000 years ago, while phylogenetic analyses reveal three novel H1 branches, termed H1v, H1w and H1x, which appear to be specific for North African populations, but whose frequencies can be extremely different even in relatively close Tuareg villages. Overall, these findings support the scenario of an arrival of haplogroup H1 in North Africa from Iberia at the beginning of the Holocene, as a consequence of the improvement in climate conditions after the Younger Dryas cold snap, followed by in situ formation of local H1 sub-haplogroups. This process of autochthonous differentiation continues in the Libyan Tuareg who, probably due to isolation and recent founder events, are characterized by village-specific maternal mtDNA lineages.     

Mitochondrial DNA reveals multiple introductions of domestic chicken in East Africa

Chicken were possibly domesticated in South and Southeast Asia. They occur ubiquitously in East Africa where they show extensive phenotypic diversity. They appeared in the region relatively late, with the first undisputed evidence of domestic chicken in Sudan, around ~ 700 BC. We reveal through a detailed analysis of mitochondrial DNA D-loop sequence diversity of 512 domestic village chickens, from four East African countries (Kenya, Ethiopia, Sudan, Uganda), the presence of at least five distinct mitochondrial DNA haplogroups. Phylogeographic analyses and inclusion of reference sequences from Asia allow us to address the origin, ways of introduction and dispersion of each haplogroup. The results indicate a likely Indian subcontinent origin for the commonest haplogroup (D) and a maritime introduction for the next commonest one (A) from Southeast and/or East Asia. Recent introgression of commercial haplotypes into the gene pool of village chickens might explain the rare presence of two haplogroups (B and C) while the origin of the last haplogroup (E) remains unclear being currently observed only outside the African continent in the inland Yunnan Province of China. Our findings not only support ancient historical maritime and terrestrial contacts between Asia and East Africa, but also indicate the presence of large maternal genetic diversity in the region which could potentially support genetic improvement programmes.     

Introducing the Algerian Mitochondrial DNA and Y-Chromosome Profiles into the North African Landscape

North Africa is considered a distinct geographic and ethnic entity within Africa. Although modern humans originated in this Continent, studies of mitochondrial DNA (mtDNA) and Y-chromosome genealogical markers provide evidence that the North African gene pool has been shaped by the back-migration of several Eurasian lineages in Paleolithic and Neolithic times. More recent influences from sub-Saharan Africa and Mediterranean Europe are also evident. The presence of East-West and North-South haplogroup frequency gradients strongly reinforces the genetic complexity of this region. However, this genetic scenario is beset with a notable gap, which is the lack of consistent information for Algeria, the largest country in the Maghreb. To fill this gap, we analyzed a sample of 240 unrelated subjects from a northwest Algeria cosmopolitan population using mtDNA sequences and Y-chromosome biallelic polymorphisms, focusing on the fine dissection of haplogroups E and R, which are the most prevalent in North Africa and Europe respectively. The Eurasian component in Algeria reached 80% for mtDNA and 90% for Y-chromosome. However, within them, the North African genetic component for mtDNA (U6 and M1; 20%) is significantly smaller than the paternal (E-M81 and E-V65; 70%). The unexpected presence of the European-derived Y-chromosome lineages R-M412, R-S116, R-U152 and R-M529 in Algeria and the rest of the Maghreb could be the counterparts of the mtDNA H1, H3 and V subgroups, pointing to direct maritime contacts between the European and North African sides of the western Mediterranean. Female influx of sub-Saharan Africans into Algeria (20%) is also significantly greater than the male (10%). In spite of these sexual asymmetries, the Algerian uniparental profiles faithfully correlate between each other and with the geography.     

Niger-Congo speaking populations and the formation of the Brazilian gene pool: mtDNA and Y-chromosome data

We analyzed sequence variation in the mitochondrial DNA (mtDNA) hypervariable segment I (HVS-I) from 201 Black individuals from two Brazilian cities (Rio de Janeiro and Porto Alegre), and compared these data with published information from 21 African populations. A subset of 187 males of the sample was also characterized for 30 Y-chromosome biallelic polymorphisms, and the data were compared with those from 48 African populations. The mtDNA data indicated that respectively 69% and 82% of the matrilineages found in Rio de Janeiro and Porto Alegre originated from West-Central/Southeast Africa. These estimates are in close agreement with historical records which indicated that most of the Brazilian slaves who arrived in Rio de Janeiro were from West-Central Africa. In contrast to mtDNA, Y-chromosome haplogroup analysis did not allow discrimination between places of origin in West or West-Central Africa. Thus, when comparing these two major African regions, there seems to be higher genetic structure with mtDNA than with Y-chromosome data.     

Y-chromosome lineages in Cabo Verde Islands witness the diverse geographic origin of its first male settlers

The Y-chromosome haplogroup composition of the population of the Cabo Verde Archipelago was profiled by using 32 single-nucleotide polymorphism markers and compared with potential source populations from Iberia, west Africa, and the Middle East. According to the traditional view, the major proportion of the founding population of Cabo Verde was of west African ancestry with the addition of a minor fraction of male colonizers from Europe. Unexpectedly, more than half of the paternal lineages (53.5%) of Cabo Verdeans clustered in haplogroups I, J, K, and R1, which are characteristic of populations of Europe and the Middle East, while being absent in the probable west African source population of Guiné-Bissau. Moreover, a high frequency of J* lineages in Cabo Verdeans relates them more closely to populations of the Middle East and probably provides the first genetic evidence of the legacy of the Jews. In addition, the considerable proportion (20.5%) of E3b(xM81) lineages indicates a possible gene flow from the Middle East or northeast Africa, which, at least partly, could be ascribed to the Sephardic Jews. In contrast to the predominance of west African mitochondrial DNA haplotypes in their maternal gene pool, the major west African Y-chromosome lineage E3a was observed only at a frequency of 15.9%. Overall, these results indicate that gene flow from multiple sources and various sex-specific patterns have been important in the formation of the genomic diversity in the Cabo Verde islands.An erratum to this article can be found at     

Genetic diversity of the Khakass gene pool: Subethnic differentiation and the structure of Y-chromosome haplogroups

The structure of Khakass gene pool has been investigated: Y-chromosome haplogroup compositions and frequencies were described in seven population samples of two basic subethnic groups, Sagai and Kachins, from three geographically separated regions of the Khakass Republic. Eight haplogroups were detected in the Khakass gene pool: C3, E, N*, N1b, N1c, R1a1a, and R1b1b1. The haplogroup spectra and the genetic diversity by haplogroups and YSTR haplotypes differed significantly between Sagai and Kachins. Kachins had a low level of gene diversity, whereas the diversity of Sagai was similar to that of other South-Siberian ethnic groups. Sagai samples from the Askizskii district were very similar to each other, and so were two Kachin samples from the Shirinskii district, while Sagai samples from the Tashtypskii district differed considerably from each other. The contribution of intergroup differences among ethnic groups was high, indicating significant genetic differentiation among native populations in Khakassia. The Khakass gene pool was strongly differentiated both by haplogroup frequencies and by YSTR haplotypes within the N1b haplogroup. The frequencies of YSTR haplotypes within the chromosome Y haplogroups N1b, N1c, and R1a1 were determined and their molecular phylogeny was investigated. Factor and cluster analysis, as well as AMOVA, suggest that the Khakass gene pool is structured by territory and subethnic groups.     

Genetic diversity of Khakassian gene pool: subethnic differensiation and the structure of Y-chromosome haplogroups,

The structure of Khakass gene pool has been investigated: compositions and frequencies of Y-chromosome haplogroups were described in seven population samples of two basic subethnic groups--Sagays and Kachins from three territorially distanced regions of Khakassia Republic. Eight haplogroups: C3, E, N*, N1b, N1c, R1a1a and R1b1b1 have been determined in Khakass gene pool. Significant differences between Sagays and Kachins were shown in haplogroup spectra and a level of genetic diversity in haplogroups and YSTR-haplotypes. Kachin samples are characterized by a low value of gene diversity, whereas the level of Sagay diversity is similar to that of other South-Siberian ethnoses. Sagay samples from Askizsky region are very similar to each other just as two Kachin samples from Shirinsky region, while Sagay samples from Tashtypsky region greatly differ from each other. A great portion of intergroup differences was determined among different ethnic groups, which testifies to significant genetic differentiation of native populations in Khakassia. Khakass gene pool is greatly differentiated both in haplogroup frequencies and in YSTR-haplotypes within N1b haplogroup. Frequencies and molecular phylogenesis of YSTR-haplotypes were revealed within N1b, N1c and R1a1 haplogroups of Y-chromosome. We carried out comparative analysis of the data obtained. The results of factor, cluster and dispersion analyses are evidence of structuredness of Khakass gene pool according to territorial-subethnic principle.     

Paternal lineages in Libya inferred from Y‐chromosome haplogroups

Many studies based on genetic diversity of North African populations have contributed to elucidate the modelling of the genetic landscape in this region. North Africa is considered as a distinct spatial‐temporal entity on geographic, archaeological, and historical grounds, which has undergone the influence of different human migrations along its shaping. For instance, Libya, a North African country, was first inhabited by Berbers and then colonized by a variety of ethnic groups like Phoenicians, Greeks, Romans, Arabs and, in recent times, Italians. In this study, we contribute to clarify the genetic variation of Libya and consequently, of North African modern populations, by the study of Libyan male lineages. A total of 22 Y‐chromosome‐specific SNPs were genotyped in a sample of 175 Libyan males, allowing the characterization of 18 Y‐chromosomal haplogroups. The obtained data revealed a predominant Northwest African component represented by haplogroup E‐M81 (33.7%) followed by J(xJ1a,J2)‐M304 (27.4%), which is postulated to have a Middle Eastern origin. The comparative study with other populations (～5,400 individuals from North Africa, Middle East, Sub‐Saharan Africa, and Europe) revealed a general genetic homogeneity among North African populations (F_ST = 5.3 %; P‐value < 0.0001). Overall, the Y‐haplogroup diversity in Libya and in North Africa is characterized by two genetic components. The first signature is typical of Berber‐speaking people (E‐M81), the autochthonous inhabitants, whereas the second is (J(xJ1a,J2)‐M304), originating from Arabic populations. This is in agreement with the hypothesis of an Arabic expansion from the Middle East, shaping the North African genetic landscape. Am J Phys Anthropol 157:242–251, 2015. © 2015 Wiley Periodicals, Inc.     

Mitochondrial DNA HVRI variation in Balearic populations

The Balearic archipelago (Majorca, Minorca, and Ibiza islands and the Chuetas, a small and inbred community of descendants of Sephardic Jews) and Valencia were studied by means of the sequencing of a 404-bp segment of hypervariable region I (HVRI) mtDNA in 231 individuals. In total, 127 different haplotypes defined by 92 variable positions were identified. The incidence of unique haplotypes was very low, especially in Ibiza and the Chuetas. A remarkable observation in the Chueta community was the high frequency (23%) of preHV-1, a Middle Eastern lineage that is closely related, though not identical, to many others found at high frequencies in different Jewish populations. The presence of this haplogroup convincingly supported the Jewish origin of the Chueta community. The studied populations showed a reduced African contribution, and no individuals were detected with North African haplogroup U6, indicating a lack of maternal contribution from the Moslem settlement to these populations. Only Ibiza showed a lower diversity, indicating a possible genetic drift effect, also supported by the historical information known about this island. The variability in the sequence of mtDNA hypervariable region I correlated well with the existing information from the populations, with the exception of that of the Y-chromosome, which could indicate a differential contribution of the maternal and paternal lineages to the genetic pool of the Balearic Islands. The phylogenetic trees showed the intermediate position of the Chueta population between the Middle Eastern and Majorcan samples, confirming the Jewish origin of this population and their Spanish admixture.     

Ethiopian mitochondrial DNA heritage: tracking gene flow across and around the gate of tears

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.     

Estimating Scandinavian and Gaelic ancestry in the male settlers of Iceland

We present findings based on a study of Y-chromosome diallelic and microsatellite variation in 181 Icelanders, 233 Scandinavians, and 283 Gaels from Ireland and Scotland. All but one of the Icelandic Y chromosomes belong to haplogroup 1 (41.4%), haplogroup 2 (34.2%), or haplogroup 3 (23.8%). We present phylogenetic networks of Icelandic Y-chromosome variation, using haplotypes constructed from seven diallelic markers and eight microsatellite markers, and we propose two new clades. We also report, for the first time, the phylogenetic context of the microsatellite marker DYS385 in Europe. A comparison of haplotypes based on six diallelic loci and five microsatellite loci indicates that some Icelandic haplogroup-1 chromosomes are likely to have a Gaelic origin, whereas for most Icelandic haplogroup-2 and -3 chromosomes, a Scandinavian origin is probable. The data suggest that 20%-25% of Icelandic founding males had Gaelic ancestry, with the remainder having Norse ancestry. The closer relationship with the Scandinavian Y-chromosome pool is supported by the results of analyses of genetic distances and lineage sharing. These findings contrast with results based on mtDNA data, which indicate closer matrilineal links with populations of the British Isles. This supports the model, put forward by some historians, that the majority of females in the Icelandic founding population had Gaelic ancestry, whereas the majority of males had Scandinavian ancestry.     

Y-chromosome analysis in Egypt suggests a genetic regional continuity in Northeastern Africa

The geographic location of Egypt, at the interface between North Africa, the Middle East, and southern Europe, prompted us to investigate the genetic diversity of this population and its relationship with neighboring populations. To assess the extent to which the modern Egyptian population reflects this intermediate geographic position, ten Unique Event Polymorphisms (UEPs), mapping to the nonrecombining portion of the Y chromosome, have been typed in 164 Y chromosomes from three North African populations. The analysis of these binary markers, which define 11 Y-chromosome lineages, were used to determine the haplogroup frequencies in Egyptians, Moroccan Arabs, and Moroccan Berbers and thereby define the Y-chromosome background in these regions. Pairwise comparisons with a set of 15 different populations from neighboring European, North African, and Middle Eastern populations and geographic analysis showed the absence of any significant genetic barrier in the eastern part of the Mediterranean area, suggesting that genetic variation and gene flow in this area follow the "isolation-by-distance" model. These results are in sharp contrast with the observation of a strong north-south genetic barrier in the western Mediterranean basin, defined by the Gibraltar Strait. Thus, the Y-chromosome gene pool in the modern Egyptian population reflects a mixture of European, Middle Eastern, and African characteristics, highlighting the importance of ancient and recent migration waves, followed by gene flow, in the region.     

Different genetic components in the Ethiopian population,identified by mtDNA and Y-chromosome polymorphisms.

Seventy-seven Ethiopians were investigated for mtDNA and Y chromosome-specific variations, in order to (1) define the different maternal and paternal components of the Ethiopian gene pool, (2) infer the origins of these maternal and paternal lineages and estimate their relative contributions, and (3) obtain information about ancient populations living in Ethiopia. The mtDNA was studied for the RFLPs relative to the six classical enzymes (HpaI, BamHI, HaeII, MspI, AvaII, and HincII) that identify the African haplogroup L and the Caucasoid haplogroups I and T. The sample was also examined at restriction sites that define the other Caucasoid haplogroups (H, U, V, W, X, J, and K) and for the simultaneous presence of the DdeI10394 and AluI10397 sites, which defines the Asian haplogroup M. Four polymorphic systems were examined on the Y chromosome: the TaqI/12f2 and the 49a,f RFLPs, the Y Alu polymorphic element (DYS287), and the sY81-A/G (DYS271) polymorphism. For comparison, the last two Y polymorphisms were also examined in 87 Senegalese previously classified for the two TaqI RFLPs. Results from these markers led to the hypothesis that the Ethiopian population (1) experienced Caucasoid gene flow mainly through males, (2) contains African components ascribable to Bantu migrations and to an in situ differentiation process from an ancestral African gene pool, and (3) exhibits some Y-chromosome affinities with the Tsumkwe San (a very ancient African group). Our finding of a high (20%) frequency of the "Asian" DdeI10394AluI10397 (++) mtDNA haplotype in Ethiopia is discussed in terms of the "out of Africa" model.     

A new topology of the human Y chromosome haplogroup E1b1 (E-P2) revealed through the use of newly characterized binary polymorphisms

Haplogroup E1b1, defined by the marker P2, is the most represented human Y chromosome haplogroup in Africa. A phylogenetic tree showing the internal structure of this haplogroup was published in 2008. A high degree of internal diversity characterizes this haplogroup, as well as the presence of a set of chromosomes undefined on the basis of a derived character. Here we make an effort to update the phylogeny of this highly diverse haplogroup by including seven mutations which have been newly discovered by direct resequencing. We also try to incorporate five previously-described markers which were not, however, reported in the 2008 tree. Additionally, during the process of mapping, we found that two previously reported SNPs required a new position on the tree. There are three key changes compared to the 2008 phylogeny. Firstly, haplogroup E-M2 (former E1b1a) and haplogroup E-M329 (former E1b1c) are now united by the mutations V38 and V100, reducing the number of E1b1 basal branches to two. The new topology of the tree has important implications concerning the origin of haplogroup E1b1. Secondly, within E1b1b1 (E-M35), two haplogroups (E-V68 and E-V257) show similar phylogenetic and geographic structure, pointing to a genetic bridge between southern European and northern African Y chromosomes. Thirdly, most of the E1b1b1* (E-M35*) paragroup chromosomes are now marked by defining mutations, thus increasing the discriminative power of the haplogroup for use in human evolution and forensics.     

The Levant versus the Horn of Africa: evidence for bidirectional corridors of human migrations

Paleoanthropological evidence indicates that both the Levantine corridor and the Horn of Africa served, repeatedly, as migratory corridors between Africa and Eurasia. We have begun investigating the roles of these passageways in bidirectional migrations of anatomically modern humans, by analyzing 45 informative biallelic markers as well as 10 microsatellite loci on the nonrecombining region of the Y chromosome (NRY) in 121 and 147 extant males from Oman and northern Egypt, respectively. The present study uncovers three important points concerning these demic movements: (1) The E3b1-M78 and E3b3-M123 lineages, as well as the R1*-M173 lineages, mark gene flow between Egypt and the Levant during the Upper Paleolithic and Mesolithic. (2) In contrast, the Horn of Africa appears to be of minor importance in the human migratory movements between Africa and Eurasia represented by these chromosomes, an observation based on the frequency distributions of E3b*-M35 (no known downstream mutations) and M173. (3) The areal diffusion patterns of G-M201, J-12f2, the derivative M173 haplogroups, and M2 suggest more recent genetic associations between the Middle East and Africa, involving the Levantine corridor and/or Arab slave routes. Affinities to African groups were also evaluated by determining the NRY haplogroup composition in 434 samples from seven sub-Saharan African populations. Oman and Egypt's NRY frequency distributions appear to be much more similar to those of the Middle East than to any sub-Saharan African population, suggesting a much larger Eurasian genetic component. Finally, the overall phylogeographic profile reveals several clinal patterns and genetic partitions that may indicate source, direction, and relative timing of different waves of dispersals and expansions involving these nine populations.     

A cryptic mitochondrial DNA link between North European and West African dogs

Domestic dogs have an ancient origin and a long history in Africa. Nevertheless, the timing and sources of their introduction into Africa remain enigmatic. Herein, we analyse variation in mitochondrial DNA(mt DNA) D-loop sequences from 345 Nigerian and 37 Kenyan village dogs plus 1530 published sequences of dogs from other parts of Africa, Europe and West Asia. All Kenyan dogs can be assigned to one of three haplogroups(matrilines; clades): A, B, and C, while Nigerian dogs can be assigned to one of four haplogroups A, B, C, and D. None of the African dogs exhibits a matrilineal contribution from the African wolf(Canis lupus lupaster). The genetic signal of a recent demographic expansion is detected in Nigerian dogs from West Africa. The analyses of mitochondrial genomes reveal a maternal genetic link between modern West African and North European dogs indicated by sub-haplogroup D1(but not the entire haplogroup D) coalescing around 12,000 years ago. Incorporating molecular anthropological evidence,we propose that sub-haplogroup D1 in West African dogs could be traced back to the late-glacial dispersals, potentially associated with human hunter-gatherer migration from southwestern Europe.     

Mitochondrial DNA structure in North Africa reveals a genetic discontinuity in the Nile Valley

Human population movements in North Africa have been mostly restricted to an east-west direction due to the geographical barriers imposed by the Sahara Desert and the Mediterranean Sea. Although these barriers have not completely impeded human migrations, genetic studies have shown that an east-west genetic gradient exists. However, the lack of genetic information of certain geographical areas and the focus of some studies in parts of the North African landscape have limited the global view of the genetic pool of North African populations. To provide a global view of the North African genetic landscape and population structure, we have analyzed ～2,300 North African mitochondrial DNA lineages (including 269 new sequences from Libya, in the first mtDNA study of the general Libyan population). Our results show a clinal distribution of certain haplogroups, some of them more frequent in Western (H, HV0, L1b, L3b, U6) or Eastern populations (L0a, R0a, N1b, I, J) that might be the result of human migrations from the Middle East, sub-Saharan Africa, and Europe. Despite this clinal pattern, a genetic discontinuity is found in the Libyan/Egyptian border, suggesting a differential gene flow in the Nile River Valley. Finally, frequency of the post-LGM subclades H1 and H3 is predominant in Libya within the H sequences, highlighting the magnitude of the LGM expansion in North Africa.     

North Indian Muslims: Enclaves of foreign DNA or Hindu converts?

The mtDNA composition of two Muslim sects from the northern Indian province of Uttar Pradesh, the Sunni and Shia, have been delineated using sequence information from hypervariable regions 1 and 2 (HVI and HVII, respectively) as well as coding region polymorphisms. A comparison of this data to that from Middle Eastern, Central Asian, North East African, and other Indian groups reveals that, at the mtDNA haplogroup level, both of these Indo-Sunni and Indo-Shia populations are more similar to each other and other Indian groups than to those from the other regions. In addition, these two Muslim sects exhibit a conspicuous absence of West Asian mtDNA haplogroups suggesting that their maternal lineages are of Indian origin. Furthermore, it is noteworthy that the maternal lineage data indicates differences between the Sunni and Shia collections of Uttar Pradesh with respect to the relative distributions of Indian-specific M sub-haplogroups (Indo Shia > Indo Sunni) and the R haplogroup (Indo Sunni > Indo Shia), a disparity that does not appear to be related to social status or geographic regions within India. Finally, the mtDNA data integrated with the Y-chromosome results from an earlier study, which indicated a major Indian genetic (Y-chromosomal) contribution as well, suggests a scenario of Hindu to Islamic conversion in these two populations. However, given the substantial level of the African/Middle Eastern YAP lineage in the Indo-Shia versus its absence in the Indo-Sunni, it is likely that this conversion was somewhat gender biased in favor of females in the Indo-Shia.     

High-resolution analysis of human Y-chromosome variation shows a sharp discontinuity and limited gene flow between northwestern Africa and the Iberian Peninsula

In the present study we have analyzed 44 Y-chromosome biallelic polymorphisms in population samples from northwestern (NW) Africa and the Iberian Peninsula, which allowed us to place each chromosome unequivocally in a phylogenetic tree based on >150 polymorphisms. The most striking results are that contemporary NW African and Iberian populations were found to have originated from distinctly different patrilineages and that the Strait of Gibraltar seems to have acted as a strong (although not complete) barrier to gene flow. In NW African populations, an Upper Paleolithic colonization that probably had its origin in eastern Africa contributed 75% of the current gene pool. In comparison, approximately 78% of contemporary Iberian Y chromosomes originated in an Upper Paleolithic expansion from western Asia, along the northern rim of the Mediterranean basin. Smaller contributions to these gene pools (constituting 13% of Y chromosomes in NW Africa and 10% of Y chromosomes in Iberia) came from the Middle East during the Neolithic and, during subsequent gene flow, from Sub-Saharan to NW Africa. Finally, bidirectional gene flow across the Strait of Gibraltar has been detected: the genetic contribution of European Y chromosomes to the NW African gene pool is estimated at 4%, and NW African populations may have contributed 7% of Iberian Y chromosomes. The Islamic rule of Spain, which began in a.d. 711 and lasted almost 8 centuries, left only a minor contribution to the current Iberian Y-chromosome pool. The high-resolution analysis of the Y chromosome allows us to separate successive migratory components and to precisely quantify each historical layer.     

Structure of the gene pool of eastern Ukrainians from Y-chromosome haplogroups

Y chromosomes from representative sample of Eastern Ukrainians (94 individuals) were analyzed for composition and frequencies of haplogroups, defined by 11 biallelic loci located in non-recombining part of the chromosome (SRY1532, YAP, 92R7, DYF155S2, 12f2, Tat, M9, M17, M25, M89, and M56). In the Ukrainian gene, pool six haplogroups were revealed: E, F (including G and I), J, N3, P, and R1a1. These haplogroups were earlier detected in a study of Y-chromosome diversity on the territory of Europe as a whole. The major haplogroup in the Ukrainian gene pool, haplogroup R1a1 (earlier designated HG3), accounted for about 44% of all Y chromosomes in the sample examined. This haplogroup is thought to mark the migration patterns of the early Indo-Europeans and is associated with the distribution of the Kurgan archaeological culture. The second major haplogroup is haplogroup F (21.3%), which is a combination of the lineages differing by the time of appearance. Haplogroup P found with the frequency of 9.6%, represents the genetic contribution of the population originating from the ancient autochthonous population of Europe. Haplogroups J and E (11.7 and 4.2%, respectively) mark the migration patterns of the Middle-Eastern agriculturists during the Neolithic. The presence of the N3 lineage (9.6%) is likely explained by a contribution of the assimilated Finno-Ugric tribes. The data on the composition and frequencies of Y-chromosome haplogroups in the sample studied substantially supplement the existing picture of the male lineage distribution in the Eastern Slav population.