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1.
Science ; 342(6160): 871-4, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24233726

RESUMO

The geographic and temporal origins of the domestic dog remain controversial, as genetic data suggest a domestication process in East Asia beginning 15,000 years ago, whereas the oldest doglike fossils are found in Europe and Siberia and date to >30,000 years ago. We analyzed the mitochondrial genomes of 18 prehistoric canids from Eurasia and the New World, along with a comprehensive panel of modern dogs and wolves. The mitochondrial genomes of all modern dogs are phylogenetically most closely related to either ancient or modern canids of Europe. Molecular dating suggests an onset of domestication there 18,800 to 32,100 years ago. These findings imply that domestic dogs are the culmination of a process that initiated with European hunter-gatherers and the canids with whom they interacted.


Assuntos
Animais Domésticos/genética , Cães/genética , Genoma Mitocondrial/genética , Animais , Sequência de Bases , Cruzamento , Europa (Continente) , Dados de Sequência Molecular , Filogenia , Lobos/genética
2.
Folia Primatol (Basel) ; 77(5): 387-92, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16912507

RESUMO

Molecular methods are being used to enforce wildlife conservation laws by identifying the species or the geographic origin of an unknown sample. However, the promising use of single-nucleotide polymorphisms (SNPs) in this field is still widely unexplored. In the present work, we have developed a reliable and easy method based on single-base extension technology for the scoring of 3 SNPs in the epsilon-globin gene that successfully identifies the primate infraorder a sample belongs to. Since primates are of high conservation concern and different infraorders are distributed in specific parts of the world, this method will serve for an initial potentially automated screening of the taxonomy and geographic origin of an unknown primate sample arriving at customs.


Assuntos
Globinas/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Primatas/classificação , Primatas/genética , Animais , Sequência de Bases , Evolução Biológica , Clonagem Molecular , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência
3.
Mol Ecol ; 15(4): 1007-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16599963

RESUMO

The badger, Meles meles, is a widely distributed mustelid in Eurasia and shows large geographic variability in morphological characters whose evolutionary significance is unclear and needs to be contrasted with molecular data. We sequenced 512 bp of the mitochondrial DNA control region in 115 Eurasian badgers from 21 countries in order to test for the existence of structuring in their phylogeography, to describe the genetic relationships among their populations across its widespread geographic range, and to infer demographic and biogeographic processes. We found that the Eurasian badger is divided into four groups regarding their mitochondrial DNA: Europe, Southwest Asia, North and East Asia, and Japan. This result suggests that the separation of badgers into phylogeographic groups was influenced by cold Pleistocene glacial stages and permafrost boundaries in Eurasia, and by geographic barriers, such as mountains and deserts. Genetic variation within phylogeographic groups based on distances assuming the Tamura-Nei model with rate heterogeneity and invariable sites (d(T-N) range: 3.3-4.2) was much lower than among them (d(T-N) range: 10.7-38.0), and 80% of the variation could be attributed to differences among regions. Spatial analysis of molecular variance (samova), median-joining network, and Mantel test did not detect genetic structuring within any of the phylogeographic groups with the exception of Europe, where 50% of variation was explained by differences among groups of populations. Our data suggest that the European, Southwest Asian, and North and East Asian badgers evolved separately since the end of Pliocene, at the beginnings of glacial ages, whereas Japanese badgers separated from continental Asian badgers during the middle Pleistocene. Endangered badgers from Crete Island, classified as Meles meles arcalus subspecies, were closely related to badgers from Southwest Asia. We also detected sudden demographic growth in European and Southwest Asian badgers that occurred during the Middle Pleistocene.


Assuntos
DNA Mitocondrial/química , Mustelidae/classificação , Mustelidae/genética , Filogenia , Migração Animal , Animais , Ásia , Sequência de Bases , Europa (Continente) , Geografia , Haplótipos , Dados de Sequência Molecular , Polimorfismo Genético
4.
Mol Ecol ; 15(2): 371-86, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16448407

RESUMO

Eurasian badgers, Meles meles, have been shown to possess limited genetic population structure within Europe; however, field studies have detected high levels of philopatry, which are expected to increase population structure. Population structure will be a consequence of both contemporary dispersal and historical processes, each of which is expected to be evident at a different scale. Therefore, to gain a greater understanding of gene flow in the badger, we examined microsatellite diversity both among and within badger populations, focusing on populations from the British Isles and western Europe. We found that while populations differed in their allelic diversity, the British Isles displayed a similar degree of diversity to the rest of western Europe. The lower genetic diversity occurring in Ireland, Norway and Scotland was more likely to have resulted from founder effects rather than contemporary population density. While there was significant population structure (F ST = 0.19), divergence among populations was generally well explained by geographic distance (P < 0.0001) across the entire range studied of more than 3000 km. Transient effects from the Pleistocene appear to have been replaced by a strong pattern of genetic isolation by distance across western Europe, suggestive of colonization from a single refugium. Analysis of individuals within British populations through Mantel tests and spatial autocorrelation demonstrated that there was significant local population structure across 3-30 km, confirming that dispersal is indeed restricted. The isolation by distance observed among badger populations across western Europe is likely to be a consequence of this restricted local dispersal.


Assuntos
Fluxo Gênico , Variação Genética , Genética Populacional , Mustelidae/genética , Animais , Europa (Continente) , Feminino , Efeito Fundador , Desequilíbrio de Ligação , Masculino , Repetições de Microssatélites
5.
Mol Ecol ; 12(2): 533-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12535103

RESUMO

The Eurasian badger (Meles meles) is a facultatively social carnivore that shows only rudimentary co-operative behaviour and a poorly defined social hierarchy. Behavioural evidence and limited genetic data have suggested that more than one female may breed in a social group. We combine pregnancy detection by ultrasound and microsatellite locus scores from a well-studied badger population from Wytham Woods, Oxfordshire, UK, to demonstrate that multiple females reproduce within a social group. We found that at least three of seven potential mothers reproduced in a group that contained 11 reproductive age females and nine offspring. Twelve primers showed variability across the species range and only five of these were variable in Wytham. The microsatellites showed a reduced repeat number, a significantly higher number of nonperfect repeats, and moderate heterozygosity levels in Wytham. The high frequency of imperfect repeats and demographic phenomena might be responsible for the reduced levels of variability observed in the badger.


Assuntos
Carnívoros/fisiologia , Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Comportamento Sexual Animal/fisiologia , Animais , Carnívoros/genética , Feminino , Heterozigoto , Masculino , Dados de Sequência Molecular , Mutação , Polimorfismo Genético , Gravidez , Prenhez , Comportamento Social , Ultrassonografia Pré-Natal , Reino Unido
6.
Physiol Biochem Zool ; 74(3): 450-60, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11331518

RESUMO

Physiological responses to nutritional and reproductive constraints were explored in a wild population of Eurasian badgers (Meles meles) inhabiting Wytham Woods, Oxfordshire, United Kingdom. We compared seasonal blood levels of lipid and protein compounds to variables describing the sex, age, body condition, wounds, testes position, and flea abundance of the badgers. We found seasonal variations in albumin/globulins and urea/creatinine ratios matched by differences in body condition. High creatinine, urea, and triglycerides levels were obtained in animals in poor nutritional condition and with low levels of body fat. The maintenance of urea/creatinine ratios indicates that the badger does not demonstrate a stage of protein conservation in periods of food scarcity during the summer or periods of cold weather. Hypercholesterolaemia, especially in fat animals, was confirmed. We also offer baseline levels of metabolites commonly used in clinical biochemistry for their further use in the analysis of the status and the management of wild badger populations.


Assuntos
Proteínas Sanguíneas/metabolismo , Carnívoros/fisiologia , Lipídeos/sangue , Estações do Ano , Tecido Adiposo/anatomia & histologia , Envelhecimento/fisiologia , Animais , Animais Selvagens , Carnívoros/sangue , Creatinina/sangue , Feminino , Masculino , Estado Nutricional , Reprodução/fisiologia , Albumina Sérica/metabolismo , Soroglobulinas/metabolismo , Triglicerídeos/sangue , Reino Unido , Ureia/sangue
7.
Pigment Cell Res ; 13(6): 467-70, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11153699

RESUMO

The sequence of the tyrosinase (Tyr) gene coding tracts has been obtained for the gorilla (Gorilla gorilla gorilla). The five exons of the gene were sequenced in three gorillas and in a normally pigmented human. The tyrosinase gene has been found to be a very conserved locus with a very low substitution rate. Some nucleotide and amino acid differences were found between the gorilla and human tyrosinase coding sequences. One of the gorillas included in the study is the only known case of albinism in a gorilla ('Snowflake'). Mutations of the TYR gene lead to Oculocutaneous Albinism type 1 (OCA1), the most common type of albinism in humans (OMIM accession number 203100). The TYR gene encodes the tyrosinase enzyme (E.C. 1.14.18.1), whose activity was found to be completely lacking in 'Snowflake', indicating that a mutation in the Tyr gene is the likely cause of his albinism. Nonetheless, no nucleotide changes were detected that could account for the lack of Tyr product or tyrosinase activity in Snowflake, and explanations of these findings are discussed.


Assuntos
Albinismo/genética , Gorilla gorilla/genética , Gorilla gorilla/fisiologia , Monofenol Mono-Oxigenase/genética , Animais , Sequência Conservada , Éxons , Deleção de Genes , Humanos , Monofenol Mono-Oxigenase/metabolismo , Mutação , RNA Mensageiro/metabolismo , Análise de Sequência de DNA
8.
Anim Behav ; 54(3): 737-46, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9299057

RESUMO

Mating and reproductive outcomes are the product of the potentially conficting strategies of breeding males and females. In a captive group of Japanese macaques, Macaca fuscata fuscatabehavioural, endocrine and genetic data were combined to assess the independent effects of male-male competition and female mate choice on mating and reproductive success. Males were ranked by social dominance and by their attractivity to females. Computer simulation and logistic regression analyses showed that male attractivity had a stronger effect than male dominance on both mating and reproductive outcome. Although male dominance and attractivity both significantly predicted mating success during fertile periods, only male attractivity significantly predicted actual male reproductive success. These results provide evidence that female mate choice can be a stronger determinant of mating and reproductive outcome in this species when male and female strategies are in conflict. The lack of a consistent correlation between male dominance rank and reproductive success in this species may be accounted for in part by female mate choice of socially subordinate males. Sires who were observed to mate with the mother during her fertile period were more likely to be socially dominant than sires who were not observed to do so. This observation suggests the existence of alternative mating strategies by subordinate males, which may also contribute to the lack of a consistent correlation between male dominance rank and reproductive success in this species.1997The Association for the Study of Animal Behaviour

10.
Am J Primatol ; 43(4): 357-60, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9403100

RESUMO

We describe seven polymorphic microsatellites isolated from a Japanese macaque (Macaca fuscata) genomic library selected for (GT)n content. The primer sets amplified from four to 11 different alleles in a sample of 14 Japanese macaques from nine different sites along the central and southern distribution of the species. These heterologous primers also detected variability in four other cercopithecine species.


Assuntos
Primers do DNA , DNA , Macaca/genética , Repetições de Microssatélites , Animais , Cercopithecinae/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética
11.
J Hered ; 88(6): 527-31, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9419895

RESUMO

Minisatellite DNA profiles using the multilocus human probe 33.6 are presented for 27 captive bobcats (Felis rufus) of documented geographic and genetic origins. The results show that 30% of the finger-printing bands present in males are sex linked. The effect of sex on band sharing was attributed to the presence of male-specific hemizygotic bands belonging to a minisatellite cluster located in the nonrecombinant region of the Y chromosome. A combination of mechanisms might drive the dynamics of minisatellite loci and allow different evolutionary rates depending on the recombinational capability of the chromosomal locations involved. We discuss the utility of sex-linked fingerprinting bands as genetic markers for the study and management of bobcats.


Assuntos
Carnívoros/genética , DNA Satélite/genética , Ligação Genética , Cromossomo Y , Animais , Impressões Digitais de DNA , Feminino , Masculino , Linhagem
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