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Contemporary Jews comprise an aggregate of ethno-religious communities whose worldwide members identify with each other through various shared religious, historical and cultural traditions (1,2). Historical evidence suggests common origins in the Middle East, followed by migrations leading to the establishment of communities of Jews in Europe, Africa and Asia, in what is termed the Jewish Diaspora (3-5). This complex demographic history imposes special challenges in attempting to address the genetic structure of the Jewish people (6). Although many genetic studies have shed light on Jewish origins and on diseases prevalent among Jewish communities, including studies focusing on uniparentally and biparentally inherited markers (7-16), genome-wide patterns of variation across the vast geographic span of Jewish Diaspora communities and their respective neighbours have yet to be addressed. Here we use high-density bead arrays to genotype individuals from 14 Jewish Diaspora communities and compare these patterns of genome-wide diversity with those from 69 Old World non-Jewish populations, of which 25 have not previously been reported. These samples were carefully chosen to provide comprehensive comparisons between Jewish and non-Jewish populations in the Diaspora, as well as with non-Jewish populations from the Middle East and north Africa. Principal component and structure-like analyses identify previously unrecognized genetic substructure within the Middle East. Most Jewish samples form a remarkably tight subcluster that overlies Druze and Cypriot samples but not samples from other Levantine populations or paired Diaspora host populations. In contrast, Ethiopian Jews (Beta Israel) and Indian Jews (Bene Israel and Cochini) cluster with neighbouring autochthonous populations in Ethiopia and western India, respectively, despite a clear paternal link between the Bene Israel and the Levant. These results cast light on the variegated genetic architecture of the Middle East, and trace the origins of most Jewish Diaspora communities to the Levant., Recently, the capacity to obtain whole-genome genotypes with the use of array technology has provided a robust tool for elucidating fine-scale population structure and aspects of demographic history (17-23). This [...]

The Egyptian Western Desert lies on an important geographic intersection between Africa and Asia. Genetic diversity of this region has been shaped, in part, by climatic changes in the Late Pleistocene and Holocene epochs marked by oscillating humid and arid periods. We present here a whole genome analysis of mitochondrial DNA (mtDNA) and high-resolution molecular analysis of nonrecombining Y-chromosomal (NRY) gene pools of a demographically small but autochthonous population from the Egyptian Western Desert oasis el-Hayez. Notwithstanding signs of expected genetic drift, we still found clear genetic evidence of a strong Near Eastern input that can be dated into the Neolithic. This is revealed by high frequencies and high internal variability of several mtDNA lineages from haplogroup T. The whole genome sequencing strategy and molecular dating allowed us to detect the accumulation of local mtDNA diversity to 5,138 [+ or -] 3,633 YBE Similarly, the Y-chromosome gene pool reveals high frequencies of the Near Eastern J1 and the North African E1b1b1b line-ages, both generally known to have expanded within North Africa during the Neolithic. These results provide another piece of evidence of the relatively young population history of North Africa. KEY WORDS Egyptian Western Desert; complete mtDNA sequences; T haplogroup; Y-chromosome; Neolithic

The first large-scale fine characterization of Tunisian H lineages clarifies that the post-Last glacial maximum expansion originating in Iberia hot only led to the resettlement of Europe but also of North Africa. We found that 46% of 81 Tunisian H lineages subscreened for 1,580 bp in mtDNA coding region were affiliated with H1 and H3 subhaplogroups, which are known to have originated in Iberia. Although no signs of local expansion were detected, which would allow a clear dating of their introduction, the younger and less diverse Tunisian H1 and H3 lineages indicate Iberia as the radiating centre. Major contributions from historical migrations to this Iberian genetic imprint in Tunisia were ruled out by the mtDNA gene pool similarity between Berber/Arab/cosmopolitan samples and some 'Andalusian' communities, settled by the descendents of the 'Moors' who once lived in Iberia for 10 centuries (between 8th and 17th centuries), before being expelled to Tunisia. KEY WORDS mtDNA; haplogroup H; Tunisia; Andalusians

The Soqotra archipelago is one of the most isolated landmasses in the world, situated at the mouth of the Gulf of Aden between the Horn of Africa and southern Arabia. The main island of Soqotra lies not far from the proposed southern migration route of anatomically modern humans out of Africa ~60,000 years ago (kya), suggesting the island may harbor traces of that first dispersal. Nothing is known about the timing and origin of the first Soqotri settlers. The oldest historical visitors to the island in the 15th century reported only the presence of an ancient population. We collected samples throughout the island and analyzed mitochondrial DNA and Y-chromosomal variation. We found little African influence among the indigenous people of the island. Although the island population likely experienced founder effects, links to the Arabian Peninsula or southwestern Asia can still be found. In comparison with datasets from neighboring regions, the Soqotri population shows evidence of long-term isolation and autochthonous evolution of several mitochondrial haplogroups. Specifically, we identified two high-frequency founder lineages that have not been detected in any other populations and classified them as a new R0a1a1 subclade. Recent expansion of the novel lineages is consistent with a Holocene settlement of the island ~6 kya. KEY WORDS mtDNA and NRY diversity; regional sampling; phylogeography; migrations; Southern Arabia

Despite its key location for population movements out of and back into Africa, Yemen has not yet been sampled on a regional level for an investigation of sub-Saharan, West Eurasian, and South Asian genetic contributions. In this study, we present mitochondrial DNA (mtDNA) data for regionally distinct Yemeni populations that reveal different distributions of mtDNA lineages. An extensive database of mtDNA sequences from North and East African, Middle Eastern and Indian populations was analyzed to provide a context for the regional Yemeni mtDNA datasets. The groups of western Yemen appear to be most closely related to Middle Eastern and North African populations, while the eastern Yemeni population from Hadramawt is most closely related to East Africa. Furthermore, haplotype matches with Africa are almost exclusively confined to West Eurasian ROa haplogroup in southwestern Yemen, although more sub-Saharan L-type matches appear in more northern Yemeni populations. In fact, Yemeni populations have the highest frequency of ROa haplotypes detected to date, thus Yemen or southern Arabia may be the site of the initial expansion of this haplogroup. Whereas two variants of the sub-Saharan haplogroup M1 were detected only in southwestern Yemen close to the Bab elMandeb Strait, different non-African M haplotypes were detected at low frequencies (~2%) in western parts of the country and at a higher frequency (7.5%) in the Hadramawt. We conclude that the Yemeni gene pool is highly stratified both regionally and temporally and that it has received West Eurasian, Northeast African, and South Asian gene flow. KEY WORDS mtDNA diversity; regional sampling; population distances; phylogeography

A matrilineal tree is developed and used to study the diversity and the structure of the mitochondrial DNA phylogeny at dawn of Homo sapiens. The early settlement of humans in Africa was shown to be matrilineally structured with small and separately evolving isolated populations.

A study to see whether inbreeding in Arabs and Berbers marriages would be reflected in the differentiation between Berber and Arab communities is presented. Concerning mtDNA, the Berber group presented a greater Eurasian contribution and no U6 haplotypes were found whereas, the Arabs showed a larger contribution of-sub-Saharan lineages and the U6 haplogroup amounted to 10%.

The Iberian peninsula is a peripheral region of Europe in close proximity to Africa. Its inhabitants have an overall mtDNA genetic landscape typical of European background, although with signs of some African influence, whose features we deemed to disclose by analyzing available mtDNA HVRI distributions and new data. We analyzed 1,045 sequences. The most relevant results are the following: (1) North African sequences (haplogroup U6) present an overall frequency of 2.39%, and sub-Saharan sequences reach 3.83%, values that are, in both cases, much higher than those generally observed in Europe; and (2) there is a substantial geographic heterogeneity in the distribution of these lineages (haplogroup L being the most frequent in the south, whereas haplogroup U6 is generally more common in the north). The analysis of the observed diversity within each haplogroup strongly suggests that both were recently introduced (in historical times). Although for haplogroup U6 the documented event that is demographically compatible is the Islamic period (beginning of the 8th century to the end of the 15th century), for haplogroup L the most probable origin is the modern slave trade (mid 15th century to the end of the 18th century). However, the observed geographic structuring for one of the haplogroups does not fit the expected distribution provided by simplistic historical considerations. In fact, although for haplogroup L the north-south increasing frequency is corroborated by historical data, the opposite trend, observed for haplogroup U6, is more difficult to reconcile with the magnitude and time span of the Islamic political and cultural influence, which lasted longer and was more intense in the south. To clarify this conundrum, we need not only a substantial increase in the amount of mtDNA data (particularly for North Africa) but also new historical data and interpretations. KEY WORDS: MTDNA, HVRI, HVRII, IBERIA, NORTH AFRICA, SUB-SAHARAN AFRICA., The first reports on mtDNA distributions in the Iberian peninsula have placed the region on the edge of European westward-decreasing genetic diversity (Comas et al. 1997; Salas et al. 1998). [...]

North African populations are considered genetically closer to Eurasians than to sub-Saharans. However, they display a considerably high mtDNA heterogeneity among them, namely in the frequencies of the U6. East African, and sub-Saharan haplogroups. In this study, we describe and compare the female gene pools of two neighboring Tunisian populations, Kesra (Berber) and Zriba (non-Berber), which have contrasting historical backgrounds. Both populations presented lower diversity values than those observed for other North African populations, and they were the only populations not showing significant negative Fu's [F.sub.s] values. Kesra displayed a much higher proportion of typical sub-Saharan haplotypes (49%, including 4.2% of M1 haplogroup) than Zriba (8%). With respect to U6 sequences, frequencies were low (2% in Kesra and 8% in Zriba), and all belonged to the subhaplogroup U6a. An analysis of these data in the context of North Africa reveals that the emerging picture is complex, because Zriba would match the profile of a Berber Moroccan population, whereas Kesra, which shows twice the frequency of sub-Saharan lineages normally observed in northern coastal populations, would match a western Saharan population except for the low U6 frequency. The North African patchy mtDNA landscape has no parallel in other regions of the world and increasing the number of sampled populations has not been accompanied by any substantial increase in our understanding of its phylogeography. Available data up to now rely on sampling small, scattered populations, although they are carefully characterized in terms of their ethnic, linguistic, and historical backgrounds. It is therefore doubtful that this picture truly represents the complex historical demography of the region rather than being just the result of the type of samplings performed so far. KEY WORDS: mtDNA VARIATION, TUNISIA, BERBERS, ARABS., Both genetic data (e.g., Plaza et al. 2003) and historical data (El Heni 1991) support the distinction of North African populations from the rest of the continent, connecting them to [...]

LUISA PEREIRA [1,2] MARIA JOAO PRATA [1,2] MARIA BRION [3] MARK A. JOBLING [4] ANGEL CARRACEDO [3] ANTONIO AMORIM [1,2] Abstract The potential of Y-chromosome biallelic marker haplotypes to infer [...]

LU[acute{I}]SA PEREIRA [1,2] Abstract Allele frequencies and a single-base substitution polymorphism for 3 short tandem repeat (STR) loci of the human myelin basic protein (MBP) gene were evaluated in North [...]

Perfluorinated compounds (PFC) are considered as emerging contaminants that attract high interest from the international scientific community. They are present in a large amount of commercialized products mainly as an [...]

Whisky is a complex and variable material, the quality of which is affected by the raw materials and processing. The overall flavor and quality results from the combination of levels [...]

Limitations in the current use of 3- and 5-[micro]m particles in HPLC has lead to interesting theories of how an expanded van Deemter curve can be utilized with smaller particles [...]

The main benefits of increased temperature are shorter retention times and a general improvement in peak efficiency and peak asymmetry. Ultra high temperature liquid chromatography (UHT-LC) is expected to show [...]