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1.
Am J Hum Genet ; 74(5): 1014-22, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15042509

RESUMO

We explored the phylogeography of human Y-chromosomal haplogroup E3b by analyzing 3401 individuals from five continents. Our data refine the phylogeny of the entire haplogroup, which appears as a collection of lineages with very different evolutionary histories, and reveal signatures of several distinct processes of migrations and/or recurrent gene flow that occurred in Africa and western Eurasia over the past 25000 years. In Europe, the overall frequency pattern of haplogroup E-M78 does not support the hypothesis of a uniform spread of people from a single parental Near Eastern population. The distribution of E-M81 chromosomes in Africa closely matches the present area of distribution of Berber-speaking populations on the continent, suggesting a close haplogroup-ethnic group parallelism. E-M34 chromosomes were more likely introduced in Ethiopia from the Near East. In conclusion, the present study shows that earlier work based on fewer Y-chromosome markers led to rather simple historical interpretations and highlights the fact that many population-genetic analyses are not robust to a poorly resolved phylogeny.


Assuntos
Cromossomos Humanos Y/genética , Emigração e Imigração , Etnicidade/genética , Variação Genética/genética , Haplótipos/genética , Filogenia , África/etnologia , Europa (Continente)/etnologia , Frequência do Gene/genética , Geografia , Humanos , Masculino , Oriente Médio/etnologia , Sibéria/etnologia , Fatores de Tempo
2.
Leg Med (Tokyo) ; 5 Suppl 1: S160-3, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12935578

RESUMO

For several years Y-chromosomal microsatellites (short tandem repeats, STRs) have been well established in forensic practice. In this context, the genetic characteristics of the Y chromosome (i.e. its paternal inheritance and lack of recombination) render STRs particularly powerful. However, genetic differences between male populations appear to be larger for Y-STRs than for autosomal STRs, a fact that is most likely due to the higher sensitivity of Y-chromosomal lineages to genetic drift (Forensic Sci Int 118 (2001) 153). The assessment of probabilities for matches between haplotyped male persons or traces/persons requires the typing of a large number of haplotypes in the appropriate reference populations. The haplotype data of a large number of European as well as South and North American populations have been collected and are continuously published online (Y-STR Haplotype Reference Database--YHRD; http://www.ystr.org). The most recent multicentric effort has led to the establishment of an Asian YHRD (http://www.ystr.org/asia) which has been available since January 2002. All databases are maintained and curated at the Institute of Legal Medicine, Humboldt-University, Berlin and will soon be fused to a global repository including populations from all continents.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y , Bases de Dados Factuais , Genética Populacional , Haplótipos , Sequências de Repetição em Tandem , Ásia , Impressões Digitais de DNA , Marcadores Genéticos , Humanos , Internet
3.
Hum Biol ; 75(1): 69-80, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12713147

RESUMO

Five APOB polymorphisms (I/D in the promoter region, XbaI [codon 24881, MspI [codon 3611], EcoRI [codon 41541, and 3' VNTRs) were studied in a population sample of 147 healthy normolipemic Bulgarians. For all biallelic loci, the observed genotype distributions do not deviate from Hardy-Weinberg equilibrium. In Bulgaria the insertion allele and the MspI+ allele of APOB presented the highest allelic frequencies (0.793 +/- 0.024 and 0.959 +/- 0.012, respectively) among the European population groups studied so far. The allele frequencies of the other two biallelic polymorphisms (XbaI and EcoRI) found in the Bulgarian population are similar to those previously described in other Caucasian populations. Analysis of the 3' VNTR polymorphism revealed 11 different alleles. Like studies in other Caucasian populations, this study found bimodal allele-size distribution and a high level of heterozygosity. The frequency of allele *31 (0.162 +/- 0.022) among Bulgarians is higher than that of any other European population group studied so far. Genetic distances between Bulgarians and each of six populations from southeastern Europe for which 3' VNTR allele frequencies are available showed an increase in the order: Albanians

Assuntos
Apolipoproteínas B/genética , Polimorfismo Genético/genética , Alelos , Bulgária , Códon , Frequência do Gene/genética , Genótipo , Humanos , Desequilíbrio de Ligação , População Branca/genética
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