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1.
Am J Phys Anthropol ; 146(1): 62-72, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21796613

RESUMO

Anthropologists have long been fascinated by the isolated hunter-gatherer populations in Southeast Asia (SEA) collectively known as "Negritos." However, the origins and affinities of these groups remain unresolved. Negritos are characterized by their short stature, dark skin color, and wiry hair, and they inhabit the Philippines, Malay Peninsula, and the Andaman Islands. Among Philippine Negritos, the Batak are of particular interest in understanding population interactions in the region due to their location on Palawan Island, which likely formed a corridor by which human migrations entered the rest of the Philippine archipelago from Island SEA. Here, we extend current understanding of the distribution of genetic diversity in Negritos by presenting the first analysis of mitochondrial DNA and Y-chromosome diversity among the Batak. We show that the Batak are genetically distinct from Negritos of the Andaman Islands and Malay Peninsula and instead bear most resemblance to geographically proximate Philippine Negritos and to non-Negrito populations from the Philippines and Island SEA. An extensive degree of recent admixture between the Batak and their neighbors is indicated by the high frequency of recently coalescing haplogroups in the Batak that are found throughout Island SEA. The comparison of results from these two loci further lends support to the hypothesis that male-biased admixture has, in particular, been a prominent feature of the interactions between the Batak and surrounding non-Negrito populations.


Assuntos
Povo Asiático/genética , Variação Genética , Filogenia , Análise de Variância , Cromossomos Humanos Y , DNA Mitocondrial/genética , Genética Populacional , Haplótipos , Humanos , Masculino , Filipinas , Dinâmica Populacional
2.
C R Biol ; 336(5-6): 273-7, 2013.
Artigo em Francês | MEDLINE | ID: mdl-23916202

RESUMO

In the Sahelian zone, the drought phenomenon, combined with anthropic factors (monoculture, bush fires, defect or deficit of manure, overgrazing, etc.), has seriously affected ecological great balances, involving a degradation of the natural resources as well as a fall in agricultural productions, pointing to a process of desertification. To face these challenges, in the course of the 8th ordinary session of the conference of the Heads of States of the African Union held in January 2007 in Addis Ababa (Ethiopia), 11 countries adopted the Panafrican project called the Green Great Wall (GGW). The total objective of the GGW is to contribute i) to the fight against the desert's advance, ii) to the development of the Saharan-Sahelian zones toward a durable management of the natural resources, and iii) to the fight against poverty. It deals with the construction of a set of zones of afforestation crossing the whole African continent in the long term (7000km of which are in the west). Even if some decisions in the launching phase the GGW must be taken quickly, one cannot do without investment in interdisciplinary research. In particular, associating fundamental research and applied research will allow us to ensure the success in the medium and long term of such a large-scale reforestation project. Research segmented in compartmentalized knowledge fields needed to get adequate tools, among which OHMi Tessékéré, initiated by INNEE (Centre national de la recherche scientifique [CNRS]), in partnership with UCAD, constitutes an example. This suitable scientific tool, capable of action flexibility, of self-financing capacity, anchored in civil society, ready to implement a pragmatic and local interdisciplinarity founded currently on the concept of socio-ecological system (SES), is the one we chose to conduct our studies on the Ferlo arid ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecologia/métodos , Ecossistema , Pesquisa , Agricultura/estatística & dados numéricos , Agricultura/tendências , Biodiversidade , Secas , Ecologia/economia , Saúde , Cooperação Internacional , Apoio à Pesquisa como Assunto , Robótica , Senegal , Fatores Socioeconômicos , Árvores , Abastecimento de Água
3.
Eur J Hum Genet ; 19(1): 89-94, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20700146

RESUMO

The Comoros Islands are situated off the coast of East Africa, at the northern entrance of the channel of Mozambique. Contemporary Comoros society displays linguistic, cultural and religious features that are indicators of interactions between African, Middle Eastern and Southeast Asian (SEA) populations. Influences came from the north, brought by the Arab and Persian traders whose maritime routes extended to Madagascar by 700-900 AD. Influences also came from the Far East, with the long-distance colonisation by Austronesian seafarers that reached Madagascar 1500 years ago. Indeed, strong genetic evidence for a SEA, but not a Middle Eastern, contribution has been found on Madagascar, but no genetic trace of either migration has been shown to exist in mainland Africa. Studying genetic diversity on the Comoros Islands could therefore provide new insights into human movement in the Indian Ocean. Here, we describe Y chromosomal and mitochondrial genetic variation in 577 Comorian islanders. We have defined 28 Y chromosomal and 9 mitochondrial lineages. We show the Comoros population to be a genetic mosaic, the result of tripartite gene flow from Africa, the Middle East and Southeast Asia. A distinctive profile of African haplogroups, shared with Madagascar, may be characteristic of coastal sub-Saharan East Africa. Finally, the absence of any maternal contribution from Western Eurasia strongly implicates male-dominated trade and religion as the drivers of gene flow from the North. The Comoros provides a first view of the genetic makeup of coastal East Africa.


Assuntos
Povo Asiático/genética , População Negra/genética , Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Emigração e Imigração , Variação Genética , África Oriental , Evolução Biológica , Comores , Evolução Cultural , Feminino , Fluxo Gênico , Genética Populacional , Humanos , Oceano Índico , Masculino
4.
Eur J Hum Genet ; 18(3): 348-53, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19826455

RESUMO

Haplogroup J1 is a prevalent Y-chromosome lineage within the Near East. We report the frequency and YSTR diversity data for its major sub-clade (J1e). The overall expansion time estimated from 453 chromosomes is 10,000 years. Moreover, the previously described J1 (DYS388=13) chromosomes, frequently found in the Caucasus and eastern Anatolian populations, were ancestral to J1e and displayed an expansion time of 9000 years. For J1e, the Zagros/Taurus mountain region displays the highest haplotype diversity, although the J1e frequency increases toward the peripheral Arabian Peninsula. The southerly pattern of decreasing expansion time estimates is consistent with the serial drift and founder effect processes. The first such migration is predicted to have occurred at the onset of the Neolithic, and accordingly J1e parallels the establishment of rain-fed agriculture and semi-nomadic herders throughout the Fertile Crescent. Subsequently, J1e lineages might have been involved in episodes of the expansion of pastoralists into arid habitats coinciding with the spread of Arabic and other Semitic-speaking populations.


Assuntos
Árabes/genética , Cromossomos Humanos Y/genética , Etnicidade/genética , Genética Populacional , Haplótipos/genética , Idioma , Loci Gênicos/genética , Geografia , Humanos , Repetições de Microssatélites/genética
5.
Transfusion ; 47(3): 402-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17319819

RESUMO

BACKGROUND: As a result of blood group polymorphism, distinctive blood types have evolved in populations around the world. In countries with large migrant populations, finding rare blood types for transfusion can be challenging. This is especially true for sub-Saharan African immigrants living in countries with predominantly European populations. This problem is further compounded by hereditary disorders such as sickle cell disease and by traditional cultural values that discourage routine donation. STUDY DESIGN AND METHODS: The purpose of this report is to describe the drive to recruit more safe rare blood type donors in a Comorian immigrant community living in Marseilles, France. With a culturally adapted message developed on an anthropologic approach and working in close collaboration with scientific and medical members of the Comorian community, it is proposed that this population be sensitized with the gift of blood. RESULTS: Targeted collection of specific sub-Saharan African blood types was achieved. Taking into account the high rate of infectious markers among products collected in this targeted collection, however, it was decided to promote blood donation in this minority by addressing people directly toward our principal blood center site. Since setup of this adapted communication, regular donors present themselves spontaneously without community pressure. Infectious markers rate is then equal to general blood donor population's rate. CONCLUSION: The results of this drive demonstrate the utility of an anthropologic approach and cultural mediation in identifying donors with specific blood types in migrant communities and recruiting second-generation donors. The techniques described in this study could also be applied to collection of other tissues including organs and peripheral blood progenitor cells in minorities.


Assuntos
População Negra , Doadores de Sangue/provisão & distribuição , Emigração e Imigração , Grupos Minoritários , Características de Residência , Antropologia Cultural , População Negra/psicologia , Doadores de Sangue/psicologia , Comores/etnologia , França/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Islamismo , Percepção
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