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1.
J Hered ; 93(6): 429-32, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12642643

RESUMO

Seventy-eight cattle samples from three Creole Caribbean islands and one Brazilian breed were analyzed for sequence variation in the hypervariable segment of the mitochondrial DNA control region. Seventy-three samples displayed Bos taurus haplotypes, and five samples exhibited haplotypes that were of Bos indicus ancestry. Phylogenetic analysis revealed that all sampled B. taurus sequences fell into two distinct clusters with separate African and European origins. European sequences were encountered in each population; however, the distribution of African haplotypes was uneven, with the highest proportion of African influence found in the Guadeloupe Creole. The reduced levels of African haplotypic variation within the Caribbean and Brazilian are consistent with prior founder effects. Additionally, genetic variation at three microsatellite loci illustrated African influence uniquely in the Guadeloupe Creole. Collectively, the data suggest that this African influence is, at least in part, attributable to the historical importation of African cattle to the Americas. Furthermore, alleles of B. indicus ancestry were detected at appreciable frequencies in all Caribbean Creole populations and may reflect zebu introgressions from either West Africa or the Indian subcontinent.


Assuntos
Bovinos/classificação , Bovinos/genética , DNA Mitocondrial/genética , África , Animais , Região do Caribe , Europa (Continente) , Amplificação de Genes , Variação Genética , Repetições de Microssatélites , Filogenia , Especificidade da Espécie
2.
Nature ; 410(6832): 1088-91, 2001 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11323670

RESUMO

The limited ranges of the wild progenitors of many of the primary European domestic species point to their origins further east in Anatolia or the fertile crescent. The wild ox (Bos primigenius), however, ranged widely and it is unknown whether it was domesticated within Europe as one feature of a local contribution to the farming economy. Here we examine mitochondrial DNA control-region sequence variation from 392 extant animals sampled from Europe, Africa and the Near East, and compare this with data from four extinct British wild oxen. The ancient sequences cluster tightly in a phylogenetic analysis and are clearly distinct from modern cattle. Network analysis of modern Bos taurus identifies four star-like clusters of haplotypes, with intra-cluster diversities that approximate to that expected from the time depth of domestic history. Notably, one of these clusters predominates in Europe and is one of three encountered at substantial frequency in the Near East. In contrast, African diversity is almost exclusively composed of a separate haplogroup, which is encountered only rarely elsewhere. These data provide strong support for a derived Near-Eastern origin for European cattle.


Assuntos
Bovinos/genética , África , Animais , Animais Selvagens , Bovinos/classificação , DNA Mitocondrial , Europa (Continente) , Variação Genética , Haplótipos , Oriente Médio , Dados de Sequência Molecular , Filogenia , Ruminantes/classificação , Ruminantes/genética
3.
Philos Trans R Soc Lond B Biol Sci ; 354(1379): 99-108; discussion 108-9, 1999 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-10091250

RESUMO

A panel of cattle bones excavated from the 1000-year-old Viking Fishamble Street site in Dublin was assessed for the presence of surviving mitochondrial DNA (mtDNA). Eleven of these bones gave amplifiable mtDNA and a portion of the hypervariable control region was determined for each specimen. A comparative analysis was performed with control region sequences from five extant Nordic and Irish cattle breeds. The medieval population displayed similar levels of mtDNA diversity to modern European breeds. However, a number of novel mtDNA haplotypes were also detected in these bone samples. In addition, the presence of a putative ancestral sequence at high frequency in the medieval population supports an early post-domestication expansion of cattle in Europe.


Assuntos
Bovinos/genética , Animais , Sequência de Bases , Osso e Ossos/química , Primers do DNA/genética , DNA Mitocondrial/genética , DNA Mitocondrial/história , DNA Mitocondrial/isolamento & purificação , Evolução Molecular , Fósseis , Variação Genética , Genética Populacional , História do Século XX , História Medieval , Irlanda , Paleontologia , Filogenia , Reação em Cadeia da Polimerase
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