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1.
Schweiz Arch Tierheilkd ; 156(1): 17-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24394174

RESUMO

This study deals with genetic analyses of an assemblage of mediaeval (13th century) cattle metapodials from Bern that had previously been osteometrically examined regarding sex, shape and wither height. The results from the genetic sexing of these small (height 100 to 120 cm) cattle correlate well with the osteometric interpretations. Some few exceptions we interpreted as cows used as draft animals with stouter bones and thus osteometrically determined as males. Two morphologically different groups of cow metatarsals however, we took as proof of the historical fact that Bern relied on livestock from different geographical origins: the town's vicinity and the alpine pastures with their favourable grazing conditions. It was not possible to distinguish them genetically. An analysis of one single nucleotide polymorphism (SNP) in the melanocortin receptor 1 (MC1R) showed that predominant coat colour most likely was red-brown. Furthermore, an analysis of the SNP in the Y-chromosomal intron UTY19 that divide modern taurine cattle in two major haplogroups (Y1 and Y2) showed that the mediaeval cattle belonged to the haplogroup Y2 with one single exception of a Y1.


Assuntos
Criação de Animais Domésticos/história , Bovinos/genética , Animais , DNA/química , DNA/genética , DNA/isolamento & purificação , Feminino , Haplótipos/genética , História Medieval , Masculino , Ossos do Metatarso/química , Polimorfismo de Nucleotídeo Único , Suíça , Cromossomo Y
3.
Anim Genet ; 38(6): 595-600, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18028515

RESUMO

Initially, domesticated African cattle were of taurine type. Today, we find both African Bos taurus and Bos indicus cattle, as well as their crossbreeds, on the continent of Africa and they all share the same set of African taurine mitochondrial DNA haplogroups. In this study, we report genetic variation as substitutions and insertions/deletions (indels) on both the X and Y chromosomes, and use the variation to assess hybridization between taurine and indicine cattle. Six African cattle breeds (four Sanga breeds, including Raya Azebu, Danakil, Caprivi, Nguni; and two Zebu breeds, including Kilimanjaro Zebu and South Kavirondo Zebu) were screened for six new X-chromosomal markers, specifically three single nucleotide polymorphisms and three indels in the DDX3X (previously DBX) and ZFX genes, and five previously identified Y-chromosomal markers in the DDX3Y (previously DBY) and ZFY genes. In total, 90 (57 bulls and 33 cows) samples from the African breeds were analysed. We identify five diagnostic haplotypes of indicine and taurine origins on both the X and Y chromosomes. For each breed, the level of indicine introgression varies; in addition to pure taurine, indicine and hybrid X-chromosome individuals, recombinant X-chromosome variants were also detected. These markers are useful molecular tools for assessing the level of indicine admixture in African cattle breeds.


Assuntos
Bovinos/genética , Polimorfismo de Nucleotídeo Único , Cromossomo X , Cromossomo Y , Animais , Feminino , Marcadores Genéticos , Haplótipos , Hibridização Genética , Masculino
4.
Anim Genet ; 38(4): 378-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17596126

RESUMO

Ancient DNA has the potential of adding the dimension of time to genetic studies. With a suitable sample set it should be possible to follow genetic changes over time as they occur. To date, only a limited number of ancient DNA studies that cover a large time span have been published, and all of these studies have used mitochondrial DNA. Here, we explore SNP typing as a way to access ancient coding nuclear genes. By targeting fragments of minimal size, we typed three polymorphic sites in 111 ancient cattle remains spanning some 4000 years. We showed that there has been a decrease in heterozygosity over time, especially since the late Middle Ages. We conclude that SNPs can be used to generate a time series for nuclear markers from ancient material, and thereby to study selection on genes over time.


Assuntos
Bovinos/genética , Evolução Molecular , Polimorfismo de Nucleotídeo Único , Alelos , Animais , Cruzamento , Frequência do Gene , Marcadores Genéticos , Heterozigoto
5.
Science ; 291(5503): 474-7, 2001 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-11161199

RESUMO

Domestication entails control of wild species and is generally regarded as a complex process confined to a restricted area and culture. Previous DNA sequence analyses of several domestic species have suggested only a limited number of origination events. We analyzed mitochondrial DNA (mtDNA) control region sequences of 191 domestic horses and found a high diversity of matrilines. Sequence analysis of equids from archaeological sites and late Pleistocene deposits showed that this diversity was not due to an accelerated mutation rate or an ancient domestication event. Consequently, high mtDNA sequence diversity of horses implies an unprecedented and widespread integration of matrilines and an extensive utilization and taming of wild horses. However, genetic variation at nuclear markers is partitioned among horse breeds and may reflect sex-biased dispersal and breeding.


Assuntos
Animais Domésticos/genética , DNA Mitocondrial/genética , Fósseis , Variação Genética , Cavalos/genética , Alelos , Criação de Animais Domésticos , Animais , Animais Selvagens/genética , Evolução Biológica , Cruzamento , Feminino , Genética Populacional , Haplótipos , Masculino , Repetições de Microssatélites , Linhagem
6.
Nature ; 404(6777): 490-3, 2000 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-10761915

RESUMO

The expansion of premodern humans into western and eastern Europe approximately 40,000 years before the present led to the eventual replacement of the Neanderthals by modern humans approximately 28,000 years ago. Here we report the second mitochondrial DNA (mtDNA) analysis of a Neanderthal, and the first such analysis on clearly dated Neanderthal remains. The specimen is from one of the eastern-most Neanderthal populations, recovered from Mezmaiskaya Cave in the northern Caucasus. Radiocarbon dating estimated the specimen to be approximately 29,000 years old and therefore from one of the latest living Neanderthals. The sequence shows 3.48% divergence from the Feldhofer Neanderthal. Phylogenetic analysis places the two Neanderthals from the Caucasus and western Germany together in a clade that is distinct from modern humans, suggesting that their mtDNA types have not contributed to the modern human mtDNA pool. Comparison with modern populations provides no evidence for the multiregional hypothesis of modern human evolution.


Assuntos
DNA Mitocondrial , Evolução Molecular , Fósseis , Hominidae/genética , Animais , Osso e Ossos , Europa (Continente) , Hominidae/classificação , Humanos , Lactente , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA
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