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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Statistical inference in population genetics using microsatellites

Csilléry, Katalin January 2009 (has links)
Statistical inference from molecular population genetic data is currently a very active area of research for two main reasons. First, in the past two decades an enormous amount of molecular genetic data have been produced and the amount of data is expected to grow even more in the future. Second, drawing inferences about complex population genetics problems, for example understanding the demographic and genetic factors that shaped modern populations, poses a serious statistical challenge. Amongst the many different kinds of genetic data that have appeared in the past two decades, the highly polymorphic microsatellites have played an important role. Microsatellites revolutionized the population genetics of natural populations, and were the initial tool for linkage mapping in humans and other model organisms. Despite their important role, and extensive use, the evolutionary dynamics of microsatellites are still not fully understood, and their statistical methods are often underdeveloped and do not adequately model microsatellite evolution. In this thesis, I address some aspects of this problem by assessing the performance of existing statistical tools, and developing some new ones. My work encompasses a range of statistical methods from simple hypothesis testing to more recent, complex computational statistical tools. This thesis consists of four main topics. First, I review the statistical methods that have been developed for microsatellites in population genetics applications. I review the different models of the microsatellite mutation process, and ask which models are the most supported by data, and how models were incorporated into statistical methods. I also present estimates of mutation parameters for several species based on published data. Second, I evaluate the performance of estimators of genetic relatedness using real data from five vertebrate populations. I demonstrate that the overall performance of marker-based pairwise relatedness estimators mainly depends on the population relatedness composition and may only be improved by the marker data quality within the limits of the population relatedness composition. Third, I investigate the different null hypotheses that may be used to test for independence between loci. Using simulations I show that testing for statistical independence (i.e. zero linkage disequilibrium, LD) is difficult to interpret in most cases, and instead a null hypothesis should be tested, which accounts for the “background LD” due to finite population size. I investigate the utility of a novel approximate testing procedure to circumvent this problem, and illustrate its use on a real data set from red deer. Fourth, I explore the utility of Approximate Bayesian Computation, inference based on summary statistics, to estimate demographic parameters from admixed populations. Assuming a simple demographic model, I show that the choice of summary statistics greatly influences the quality of the estimation, and that different parameters are better estimated with different summary statistics. Most importantly, I show how the estimation of most admixture parameters can be considerably improved via the use of linkage disequilibrium statistics from microsatellite data.
32

Modification of the structure of wild boar populations by hunting and influence on reproductive processes / Modification de la structure des populations de sangliers par la chasse et influence sur les processus de reproduction

Gayet, Thibault 13 July 2018 (has links)
Le sanglier (Sus scrofa scrofa) est une espèce à part entière. C'est une espèce de gibier particulièrement appréciée des chasseurs, un cauchemar pour les agriculteurs et un sujet de débat pour la société en général. La multiplication par dix des populations au cours des dernières décennies en France et dans toute l'Europe, malgré une pression de chasse accrue, a engendré de nombreux conflits entre les humains et la faune sauvage. Le sanglier est responsable de grandes pertes économiques dues aux collisions avec les véhicules, à la transmission de maladies et de dommages aux cultures et écosystèmes. L'amélioration des stratégies de gestion devient un intérêt majeur pour éviter, ou contrôler, de tels conflits. La récolte d'informations sur l'espèce problématique est un premier pas vers de bonnes stratégies de gestion. L'objectif de mon travail est, dans un premier temps, de caractériser le système d’appariement du sanglier et d'identifier certains paramètres influençant les processus de reproduction, notamment la chasse. Dans un deuxième temps, mon travail se concentre sur l'étude de l'influence du système d’appariement sur les traits d'histoire de vie du sanglier. Mes recherches sont basées sur l'étude de plusieurs populations contrastées dans leurs pratiques de chasse et sur des données longitudinales d'une population intensivement suivie. L'étude est basée sur des données recueillies sur des sangliers tués à la chasse. Les génotypes ont été obtenus pour les femelles gestantes et leur portée et des analyses de paternité ont été réalisées pour mesurer le nombre de pères dans une portée et estimer les taux de paternité multiples (proportion de portées engendrées par plus d'un père). J'ai été en mesure de montrer que le système d’appariement est principalement de promiscuite (plusieurs mâles s'accouplent avec plusieurs femelles) contrastant avec la polygynie (un mâle dominant monopolisant un groupe de femelles) habituellement décrite chez cette espèce. De plus, les processus de reproduction, estimés par le nombre de partenaires d'une femelle et les taux de paternité multiples, sont influencés par les variations de chasse dans une population. J'ai aussi montré que le nombre de pères avait un effet positif sur la fécondité des femelles. Des taux élevés de paternité multiple et une grande diversité génétique ont été constatés ensemble dans une population fortement chassée, ce qui suggère que la paternité multiple peut tamponner les goulots d'étranglement annuels. Cependant, l'augmentation du nombre de père n'est pas associée à une augmentation de la variation intraportée / The wild boar (Sus scrofa scrofa) is a peculiar species. It is an appreciated game species for hunters, a nightmare for farmers and a subject of debate for the society in general. The tenfold increase of the population over the last decades in France and all over Europe, despite increased hunting pressure, generated great human-wildlife conflict. The wild boar is responsible for great economic losses due to vehicle collision, diseases transmission and damaged crops and ecosystems. Improving management strategies becomes a prime interest to avoid such conflicts, or at least keep them under control. Obtaining information on the species is a first step toward good management strategies. The objective of my work is, in a first part, to characterize the mating system of the wild boar and to identify some parameters, especially hunting, influencing the reproductive processes. The second part focus on the investigation of the influence of the mating system on wild boar life history traits. My researches are based on the study of several populations contrasting in their hunting practices and on longitudinal data of a highly monitored population. The study is based on data collected on wild boars killed by hunting. Genotypes were obtained for pregnant females and their litter and paternity analyses were realized to measure the number of fathers in a litter and estimate multiple paternity rates (proportion of litter sired by more than one father). I was able to show that the mating system is mainly promiscuous (several males mate with several females) contrasting with the polygyny (a dominant male monopolizing a group of females) usually described in this species. Moreover, reproductive processes, estimated by the number of mates of a female and the multiple paternity rates, are influenced by hunting variations in a population. I also showed that number of fathers has positive effect on female fecundity. High rates of multiple paternity together with high genetic diversity were found in a heavily hunted population, suggesting multiple paternity may buffer yearly bottlenecks. However, the increase of number of fathers is not associated with increase of within-litter variation
33

Association Of The Cyp2e1, Fmo3, Nqo1, Gst And Nos3 Genetic Polymorphisms With Ischemic Stroke Risk In Turkish Population

Ozcelik, Aysun 01 December 2011 (has links) (PDF)
Stroke, a major cause of death and disability, is described as interruption or severe reduction of blood flow in cerebral arteries. Oxidative stress plays an important role in the pathogenesis of atherosclerosis and carotid atherosclerosis is a risk factor for stroke. Combination of multiple environmental and genetic risk factors is thought to increase susceptibility to the development of this disease. Therefore, investigation of the polymorphisms of drug metabolizing enzymes is of crucial importance to determine the molecular etiology of the disease. The main objective of this study was to investigate the possible association between polymorphisms of enzymes causing oxidative stress (CYP2E1, FMO3 and NOS3) and enzymes protecting against oxidative stress (GST and NQO1), and the pathogenesis of atherosclerosis and ischemic stroke risk. The study population consisted of 245 unrelated ischemic stroke patients and 145 healthy control subjects. There was no statistically difference between the patient and control groups in terms of age and gender. Hypertension, diabetes, smoking and obesity were found to be at least 2 times more common in stroke patients than controls. While total cholesterol, triglyceride and LDL-cholesterol level were higher in stroke patients, HDL-cholesterol level was lower in stroke patients when compared to controls. In the case-control analyses for the risk of ischemic stroke, CYP2E1*5B mutant allele, *5B was found to be associated with the development of disease (Odds Ratio / OR=7.876, 95%CI=1.025-60.525, P=0.019). In addition, significant difference was observed between stroke patients and controls with respect to CYP2E1*5B genotype distribution (OR=0.869, 95%CI=1.044-62.339, P=0.017). On the other hand, in the NQO1*2 polymorphism, together with NQO1 heterozygote (*1*2), NQO1 homozygote mutant (*2*2) genotype was found protective against ischemic stroke (OR=0.627, 95%CI=0.414-0.950, P=0.027). The risk of hypertensive individuals having stroke was highest in the FMO3 472GA group (OR=6.110, P=0.000). In diabetics, GSTP1 313AG genotype was found to be the highest risk factor for stroke (OR=3.808 P=0.001). On the other hand, NQO1 *1*2 heterozygote genotype was associated with 5 times increased risk for stroke in smokers (OR=5.000, P=0.000). In addition GSTM1 present genotype constituted 8 times increased stroke risk in obese individuals (OR=8.068, P=0.001). Logistic regression analysis revealed that hypertension, diabetes mellitus, obesity and smoking were significant risk factors for stroke. On the other hand, HDL-cholesterol and having NQO1 *1*2 heterozygote genotype were found to be protective factors against stroke.
34

Investigation into population genetic structure of eel Anguilla anguilla (L.) and perch Perca fluviatilis L. within the context of anthropogenic activity / Ungurio Anguilla anguilla (L.) ir ešerio Perca fluviatilis L. populiacinės-genetinės struktūros tyrimai antropogeninio poveikio kontekste

Ragauskas, Adomas 25 June 2013 (has links)
Seeking for a sustainable exploitation of the populations of commercialy valuable fish species without causing danger to their genetic resources it is necessary to amass extensive data about the population genetic structure of this fish species. When preparing the thesis a total of 221 eels and 262 perch were analysed. Fish samples collected in Lithuania and Latvia were studied using microsatellite DNA, the mtDNA D-loop region and mtDNA cyt b markers. Original primer pairs Ang1 and Ang2 have been designed for the mtDNA analysis of the eel. On the basis of the Anguilla genus species mtDNA D-loop region data obtained during work it can be stated that inland and territorial water bodies of Lithuania contain no A. japonica and A. rostrata species. The molecular investigations carried out indicate that the population genetic structure of the European eel is characterized by the genetic mosaic, which is formed due to the existence of reproductively isolated groups. Statistically significant genetic differentiation between the eel groups naturally recruited to Lithuania and Latvia and introduced to Lithuanian lakes has not been determined (p > 0.05). However, the eels stocked into different lakes of Lithuania differ in their genetic diversity. Pairwise comparisons of the Lithuanian and Latvian perch populations based on the mtDNA D-loop region data revealed that the perch population of Lake Drūkšiai was statistically significantly (p < 0.05) different from all other perch... [to full text] / Siekiant tvariai eksploatuoti verslinių žuvų populiacijas nesukeliant pavojaus jų genetiniams resursams būtina sukaupti daug duomenų apie šių rūšių populiacinę-genetinę struktūrą. Iš viso tyrimams panaudoti 221 unguriai ir 262 ešeriai. Lietuvoje ir Latvijoje surinkti žuvų audinių pavyzdžiai tirti naudojant mikrosatelitinės DNR, mtDNR D-kilpos regiono ir mtDNR cyt b žymenis. Ungurių mtDNR analizei sukurtos originalios Ang1 ir Ang2 pradmenų poros. Remiantis disertacinio darbo metu atliktais Anguilla genties rūšių mtDNR D-kilpos regiono tyrimais, galima teigti, jog šiuo metu A. japonica ir A. rostrata rūšių, tiek tirtuose Lietuvos vidaus vandens telkiniuose, tiek Lietuvos teritoriniuose vandenyse nėra. Atlikti molekuliniai tyrimai rodo, kad europinio upinio ungurio populiacinė-genetinė struktūra pasižymi genetine mozaika, kurios susiformavimą lemia reproduktyviai izoliuotos grupės. Tarp natūraliai į Lietuvą ir Latviją atplaukusių ir introdukuotų Lietuvos ežeruose ungurių grupių statistiškai patikima genetinė diferenciacija nenustatyta (p > 0,05), tačiau skirtinguose Lietuvos ežeruose gyvenantys unguriai pasižymi skirtinga genetine įvairove. Atliktų Perca fluviatilis mtDNR D-kilpos regiono tyrimų rezultatai rodo, jog Drūkšių ežero ešerių populiacija statistiškai patikimai (p < 0,05) skiriasi nuo visų kitų Lietuvos ir Latvijos ešerių populiacijų. Nustatyta, kad nuo Lietuvos pietvakarinės dalies iki Latvijos centrinės dalies plyti kelių skirtingų ešerių genetinių linijų kontaktinė... [toliau žr. visą tekstą]
35

Ungurio Anguilla anguilla (L.) ir ešerio Perca fluviatilis L. populiacinės-genetinės struktūros tyrimai antropogeninio poveikio kontekste / Investigation into population genetic structure of eel Anguilla anguilla (L.) and perch Perca fluviatilis L. within the context of anthropogenic activity

Ragauskas, Adomas 25 June 2013 (has links)
Siekiant tvariai eksploatuoti verslinių žuvų populiacijas nesukeliant pavojaus jų genetiniams resursams būtina sukaupti daug duomenų apie šių rūšių populiacinę-genetinę struktūrą. Iš viso tyrimams panaudoti 221 unguriai ir 262 ešeriai. Lietuvoje ir Latvijoje surinkti žuvų audinių pavyzdžiai tirti naudojant mikrosatelitinės DNR, mtDNR D-kilpos regiono ir mtDNR cyt b žymenis. Ungurių mtDNR analizei sukurtos originalios Ang1 ir Ang2 pradmenų poros. Remiantis disertacinio darbo metu atliktais Anguilla genties rūšių mtDNR D-kilpos regiono tyrimais, galima teigti, jog šiuo metu A. japonica ir A. rostrata rūšių, tiek tirtuose Lietuvos vidaus vandens telkiniuose, tiek Lietuvos teritoriniuose vandenyse nėra. Atlikti molekuliniai tyrimai rodo, kad europinio upinio ungurio populiacinė-genetinė struktūra pasižymi genetine mozaika, kurios susiformavimą lemia reproduktyviai izoliuotos grupės. Tarp natūraliai į Lietuvą ir Latviją atplaukusių ir introdukuotų Lietuvos ežeruose ungurių grupių statistiškai patikima genetinė diferenciacija nenustatyta (p > 0,05), tačiau skirtinguose Lietuvos ežeruose gyvenantys unguriai pasižymi skirtinga genetine įvairove. Atliktų Perca fluviatilis mtDNR D-kilpos regiono tyrimų rezultatai rodo, jog Drūkšių ežero ešerių populiacija statistiškai patikimai (p < 0,05) skiriasi nuo visų kitų Lietuvos ir Latvijos ešerių populiacijų. Nustatyta, kad nuo Lietuvos pietvakarinės dalies iki Latvijos centrinės dalies plyti kelių skirtingų ešerių genetinių linijų kontaktinė... [toliau žr. visą tekstą] / Seeking for a sustainable exploitation of the populations of commercialy valuable fish species without causing danger to their genetic resources it is necessary to amass extensive data about the population genetic structure of this fish species. When preparing the thesis a total of 221 eels and 262 perch were analysed. Fish samples collected in Lithuania and Latvia were studied using microsatellite DNA, the mtDNA D-loop region and mtDNA cyt b markers. Original primer pairs Ang1 and Ang2 have been designed for the mtDNA analysis of the eel. On the basis of the Anguilla genus species mtDNA D-loop region data obtained during work it can be stated that inland and territorial water bodies of Lithuania contain no A. japonica and A. rostrata species. The molecular investigations carried out indicate that the population genetic structure of the European eel is characterized by the genetic mosaic, which is formed due to the existence of reproductively isolated groups. Statistically significant genetic differentiation between the eel groups naturally recruited to Lithuania and Latvia and introduced to Lithuanian lakes has not been determined (p > 0.05). However, the eels stocked into different lakes of Lithuania differ in their genetic diversity. Pairwise comparisons of the Lithuanian and Latvian perch populations based on the mtDNA D-loop region data revealed that the perch population of Lake Drūkšiai was statistically significantly (p < 0.05) different from all other perch... [to full text]
36

The Impact of Migration on the Evolution and Conservation of an Endemic North American Passerine: Loggerhead Shrike (Lanius ludovicianus)

CHABOT, AMY A 26 January 2011 (has links)
Migration acts as a selective force on the ecology and evolutionary trajectory of species, as well as presenting fundamental challenges for conservation. My thesis examines the impact of migration by exploring patterns of differentiation among and within migratory and non-migratory populations of the Loggerhead Shrike (Lanius ludovicianus). First, I use morphological, genotypic, stable isotope and leg band recovery data to quantify migratory connectivity in the species. Comparison across markers reveals a generally concordant pattern of moderate connectivity to the Gulf Coast, but overall mixing among populations on the wintering grounds. Combining data from multiple markers in a Bayesian framework improves the resolution of assignment of wintering birds to a breeding ground origin. Information on the species’ migratory patterns provides an explicit framework for interpreting patterns of genetic and ecological variation. I test two hypotheses regarding the interaction of gene flow and migratory habit: (1) migration facilitates gene flow; and (2) gene flow will occur most often along the axis of migration. Genetic population structure in migratory populations is weaker than in non-migratory populations, with gene flow facilitated by dispersal movements of females and first year breeders. As predicted, gene flow occurs most often along the north-south axis of migration, likely due either to opportunistic settling of dispersers or potentially, pairing on the wintering grounds. I investigate variation in the extent and scheduling of moult in relation to underlying genetic differences among populations, age, sex, body size, food availability and migratory habit. I find a pattern of interrupted moult across migratory populations, which may represent a trade-off between time allocated to breeding versus molt and migration. Loggerhead Shrikes in eastern and more southerly migratory populations undergo a greater extent of their moult on the breeding grounds and non-migratory individuals undergo a more extensive pre-formative moult than migratory individuals. I interpret this as suggesting a trade-off between resources allocated to molt versus those required for reproduction. / Thesis (Ph.D, Biology) -- Queen's University, 2011-01-25 15:54:36.593
37

Inferring biogeography from the evolutionary history of the giant freshwater prawn (macrobrachium rosenbergii)

de Bruyn, Mark January 2006 (has links)
The discipline of historical biogeography seeks to understand the contribution of earth history to the generation of biodiversity. Traditionally, the study of historical biogeography has been approached by examining the distribution of a biota at or above the species level. While this approach has provided important insights into the relationship between biological diversity and earth history, a significant amount of information recorded below the species level (intraspecific variation), regarding the biogeographical history of a region, may be lost. The application of phylogeography - which considers information recorded below the species level - goes some way to addressing this problem. Patterns of intraspecific molecular variation in wide-ranging taxa can be useful for inferring biogeography, and can also be used to test competing biogeographical hypotheses (often based on the dispersal-vicariance debate). Moreover, it is argued here that phylogeographical studies have recently begun to unite these two disparate views, in the recognition that both dispersal and vicariance have played fundamental roles in the generation of biodiversity. Freshwater dependent taxa are ideal model organisms for the current field of research, as they reflect well the underlying biogeographical history of a given region, due to limited dispersal abilities - their requirement for freshwater restricts them. To this end, this study documented the phylogeographical history of the giant freshwater prawn (Macrobrachium rosenbergii) utilising both mitochondrial (COI & 16S) and nuclear (microsatellite) markers. Samples (n = ~1000) were obtained from across most of the natural distribution of M. rosenbergii [Southern and South East (SE) Asia, New Guinea, northern Australia]. Initial phylogenetic analyses identified two highly divergent forms of this species restricted to either side of Huxley's extension of Wallace's Line; a pattern consistent with ancient vicariance across the Makassar Strait. Subsequent analyses of molecular variation within the two major clades specifically tested a number of biogeographical hypotheses, including that: 1.) a major biogeographical transition zone between the Sundaic and Indochinese biotas, located just north of the Isthmus of Kra in SE Asia, results from Neogene marine transgressions that breached the Isthmus in two locations for prolonged periods of time; 2.) Australia's Lake Carpentaria [circa 80 000 - 8 500 before present (BP)] facilitated genetic interchange among freshwater organisms during the Late Pleistocene; 3.) sea-level fluctuations during the Pleistocene constrained evolutionary diversification of M. rosenbergii within the Indo-Australian Archipelago (IAA); and 4.) New Guinea's Fly River changed course from its current easterly outflow to flow westwards into Lake Carpentaria during the Late Pleistocene. The results support hypotheses 1-3, but not 4. The potential for phylogeography to contribute significantly to the study of historical biogeography is also discussed.
38

Variabilidade genética e química entre e dentro de populações de Casearia sylvestris Sw. (Salicaceae) no estado de São Paulo

Cavallari, Marcelo Mattos [UNESP] 22 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-22Bitstream added on 2014-06-13T19:42:39Z : No. of bitstreams: 1 cavallari_mm_dr_botib.pdf: 2341412 bytes, checksum: 25cb49e35e82d3a208a4d24cb3f50d39 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve como objetivo produzir ferramentas e informações úteis para a conservação e exploração racional de Casearia sylvestris Sw. (Salicaceae), uma espécie que produz diterpenos clerodânicos de grande importância farmacológica (casearinas), e que é explorada por extrativismo. Tal objetivo foi alcançado através do desenvolvimento de marcadores microssatélites específicos para C. sylvestris e de um estudo da diversidade genética e química existente entre e dentro de populações do Estado de São Paulo. Tradicionalmente são reconhecidas duas variedades em C. sylvestris (var. sylvestris e var. lingua), o que é motivo de debate devido à existência de formas intermediárias. Este trabalho objetivou, adicionalmente, contribuir com argumentos genéticos para esta discussão. Foi construída uma biblioteca enriquecida em microssatélites, a partir da qual obtiveram-se e validaram-se dez pares de iniciadores (primers) microssatélites específicos para C. sylvestris. Estes pares de iniciadores foram utilizados para o estudo da estrutura genética de populações de C. sylvestris através da amostragem de 376 indivíduos em nove populações distribuídas em quatro ecossistemas (Floresta Ombrófila Densa, Floresta Estacional Semidecidual, Cerrado e ecótonos). As duas variedades foram amostradas de acordo com sua distribuição nestes ecossistemas. A genotipagem dos indivíduos para os locos amostrados foi realizada através de eletroforese em gel de acrilamida lido a 700 e 800 nm por um seqüenciador IR2-DNA Analyser (LI-COR). Os dados foram analisados através de abordagens frequentistas, bayesianas e baseadas na teoria de coalescência, utilizando-se diversos programas computacionais. Para o estudo da diversidade química, as mesmas populações foram amostradas, selecionando-se 12 indivíduos por população, totalizando 108 indivíduos. Adicionalmente, foram... / This work aimed obtaining tools and information for the conservation and rational exploitation of Casearia sylvestris Sw. (Salicaceae), a tree species which produces casearins, pharmacologically important clerodane diterpenes. This goal was achieved through the development of a set of polymorphic microsatellite markers, and through the study of chemical and genetic diversity in populations of C. sylvestris from São Paulo State. Also, we aimed contributing for the debate on the existence of two varieties within this species (var. sylvestris e var. lingua). A genomic library was constructed and 10 primer pairs were obtained. Those primers were utilized for a population genetic structure analysis, in which 376 individuals from nine populations distributed on four different ecosystems (Evergreen Atlantic Forest, Semideciduous Atlantic Forest, Cerrado and ecotones) were sampled. The two varieties were sampled according to its distribution among these populations. Genotyping was performed at 700 and 800 nm by electrophoresis on an IR2-DNA Analyser (LI-COR). The data were analyzed through frequentist, Bayesian and coalescence-based approaches, through the use of several softwares. Chemical diversity was studied by sampling in the same populations (12 individuals per population, i.e. 108 individuals). Also, cuttings of these individuals were prepared, aiming to verify its’ chemical compounds after a year of green-house cultivation. Cuttings’ rooting was problematic and a methodology was developed. Only 46 cuttings survived. Casearins from these 154 individuals (108 + 46) were extracted and analyzed by HPLC. Genetic analysis results suggests a partial genome duplication, as more than two alleles for the same locus were observed in 8% of var. sylvestris individuals and in 70% of var. lingua individuals. Additional studies are necessary to verify the hypothesis of partial genome duplication... (Complete abstract click electronic access below)
39

Parentesco e diferenciação genética em queixadas (Tayassu pecari) do Pantanal Matogrossense (MS) / Relatedness and genetic differentiation of white-lipped peccaries (Tayassu pecari) from the Brazilian Pantanal

Danilo Aqueu Rufo 17 September 2012 (has links)
Queixadas (Tayassu pecari) são mamíferos ungulados sociais que vivem em bandos que facilmente ultrapassam 100 indivíduos. Os objetivos do presente estudo foram: 1) avaliar se há relação entre o parentesco e a estrutura social das queixadas e 2) re-analisar se há diferenciação genética entre queixadas de duas localidades do Pantanal do Mato Grosso do Sul, utilizando maior amostragem de indivíduos e de marcadores microssatélites. Foram genotipadas 184 amostras de queixadas (53 da Fazendo Rio Negro, RN e 131 da Fazenda Santa Emília, SE) para 15 microssatélites. O número de alelos encontrados variou de 2 a 12, com média de 4,60 em RN e 5,07 em SE. Embora o número de alelos médio foi significativamente maior em SE do que em RN (p < 0,05), a riqueza alélica média (4,59 na RN e 4,69 na SE) e as heterozigosidades médias observada e esperada (0,50 e 0,53 na RN e 0,55 e 0,55 na SE, respectivamente) foram similares em ambas as localidades, (p > 0,05). A mediana do coeficiente de parentesco em ambas as localidades foi significativamente maior entre os indivíduos de mesmo grupo de coleta do que entre os indivíduos de grupos de coleta diferentes, tanto para a análise incluindo todos os indivíduos como para a análise sem os indivíduos jovens. Isso sugere que tal resultado não é influenciado por possível captura de um jovem com seu progenitor. De forma similar, a mediana do coeficiente de parentesco considerando o sexo dos indivíduos (macho/macho, macho/fêmea e fêmea/fêmea) dentro e entre os grupos de coleta foi significativamente maior entre as categorias dentro dos grupos de coleta do que entre os grupos de coleta, tanto com os indivíduos jovens como sem os indivíduos jovens. Tais resultados sugerem que o parentesco possui influência na formação dos grupos sociais. O valor de FST encontrado entre as localidades foi de 0,017 e significativamente diferente de zero e o valor de DEST foi de 0,015. A análise Bayesiana, assumindo o modelo de mistura entre as populações e frequências alélicas correlacionadas, apontou o valor de K=1 como sendo o mais provável. Quando a localidade de coleta foi informada, o valor de K mais provável foi de 2 e os agrupamentos corresponderam exatamente às localidades amostradas. Esses resultados indicam que as queixadas das duas localidades estudadas compõem duas populações com alto fluxo gênico entre elas / White-lipped peccaries (Tayassu pecari) are social ungulates that live in herds of usually more than 100 individuals. The aims of the present study were: 1) to evaluate whether there is any correlation between relatedness and social structure of white-lipped peccaries and 2) to re-examine whether there is significant genetic differentiation in white-lipped peccaries from two adjacent locations of the Brazilian Pantanal, based on a larger sample of individuals and of microsatellite markers. In total, 184 peccaries (53 from Fazenda Rio Negro, RN and 131 from Fazenda Santa Emilia, SE) were genotyped for 15 microsatellites. The number of alleles observed per microsatellite varied from 2 to 12, with a mean of 4.60 in RN and 5.07 in SE. Although the mean number of alleles was significantly higher in SE than in RN (p < 0.05), the mean allelic richness (4.59 in RN and 4.69 in SE) and mean observed and expected heterozygosities (0.50 and 0.53 in RN and 0.55 and 0.55 in SE, respectively) were similar in both locations (p > 0,05). The median of the coefficient of relatedness in both locations was significantly higher between individuals captured together than between individuals from different capture groups, both for the analyses including all individuals as for the analyses without the youngsters. This suggests that this result is not influenced by the possible capture of a young with its parent. Similarly, the median of the coefficient of relatedness according to gender (male vs. male, male vs. female, and female vs. female) was significantly higher within than among capture groups, including or excluding young individuals. Those results suggest that relatedness has some importance in the social structure of white-lipped peccaries. The FST between the locations was 0.017 and significantly different from zero and the DEST was 0.015. The Bayesian analysis, assuming the model of population mixture and correlated allele frequencies, showed that the most likely K was 1. When the collection site was included in the analysis, the most likely value of K was 2 and the clusters corresponded exactly to the locations of origin of the samples. Those results suggest that the white-lipped peccaries of the two sites studied comprise two populations with high levels of gene flow between them
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Estrutura genética de três membros do complexo Triatoma brasiliensis que ocorrem no estado da Bahia, com enfoque principal para Triatoma sherlocki papa et al., 2002 (Hemiptera, Heteroptera, Reduviidae, Triatominae) / Genetic structure of three members of Triatoma brasiliensis complex occurning in the state of Bahia with main focus for Triatoma sherlocki Papa et al., 2002 (Hemiptera, Heteroptera, Reduviidae, Triatominae)

Mendonça, Vagner José, 1978- 20 August 2018 (has links)
Orientadores: João Aristeu da Rosa, Carlos Eduardo Almeida / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T07:28:24Z (GMT). No. of bitstreams: 1 Mendonca_VagnerJose_D.pdf: 2848231 bytes, checksum: 6e470eb55a7fddfe925c1a2be00db939 (MD5) Previous issue date: 2011 / Resumo: Triatoma sherlocki, espécie primeiramente coletada por Cerqueira, 1975, tem distribuição registrada na região do município de Gentio do Ouro, Centro Norte do Estado da Bahia, Brasil. Populações intradomiciliares dessa espécie foram encontradas em um assentamento de garimpo em Gentio do Ouro, conhecido como Encantado. Em sua localidade tipo (Santo Inácio) invasões domiciliares são frequentes, mas não foi constatado qualquer indício de domiciliação, portanto informações sobre a sua biologia e aspectos epidemiológicos quanto à transmissão de Trypanosoma cruzi se fazem necessárias. O objetivo central deste trabalho foi verificar se o fator genético poderia estar envolvido no processo de domiciliação de T. sherlocki e se as populações provenientes de ambientes antropizados poderiam apresentar identidade genética. Coletas em ambientes estritamente silvestres e em áreas antropizados nas localidades Santo Inácio e Encantado foram efetuadas entre 2008 e 2009. A análise da variabilidade genética das populações coletadas de T. sherlocki foi verificada por meio de sequenciamento de um fragmento do gene mitocondrial Citocromo B e a estrutura genética foi avaliada utilizando Análise de Variância Molecular (AMOVA). Exemplares de T. sherlocki foram coletados em nove localidades, duas antrópicas, denominadas "Encantado 1" e "Santo Inácio 1", e as demais estritamente silvestres denominadas "Encantado 2", "Santo Inácio 2", "Gentio do Ouro 1", "Gentio do Ouro 2", "Gentio do Ouro 3", "Gentio do Ouro 4" e "Gentio do Ouro 5". Somente na localidade de "Encantado 1" existem registros de capturas de ninfas e adultos no intradomicílo. Em Santo Inácio 1, segundo a Secretaria de Saúde de Gentio do Ouro, casos de invasões esporádicas são frequentes apenas por exemplares adultos. Foram obtidas 292 sequências de 565 pares de bases do fragmento do gene mitocondrial Cit B e 63 haplótipos foram encontrados. Os valores de diversidade haplotípica variaram de 0.602 para a localidade "Gentio do Ouro 4" até 0.820 para a localidade "Gentio do Ouro 2". Os resultados obtidos por AMOVA demonstraram que o agrupamento de populações por distância geográfica variou mais entre os grupos (11.13%) do que entre populações dentro dos grupos (2.83%). As análises baseadas em agrupamentos ecológicos, isto é, silvestres versus antrópicos, variaram em 13.39% entre as populações dentro desses grupos, portanto, sem estruturação genética para esses agrupamentos. Esses resultados não suportam a hipótese de dispersão passiva para a formação de colônias intradomiciliares em Encantado 1 a partir de Santo Inácio 1 e sugerem que a colonização das habitações em Encantado 1 ocorre a partir de focos silvestres adjacentes. Como as populações de Encantado 1 e 2 apresentaram relativo grau de diferenciação genética quando comparadas às demais, a possibilidade do fator genético estar envolvido na colonização dos domicílios em Encantado deve ser considerada. As análises de populações de T. juazeirensis e de T. melanica, membros do complexo T. brasiliensis, foram conduzidas com a mesma abordagem utilizada para o estudo da estrutura genética de T. sherlocki. A variação entre as populações T. sherlocki e T. melanica são compatíveis com a diferenciação intraespecífica, ao passo que para T. juazeirensis encontrou-se alta diferenciação genética entre populações da Localidade Tipo (Juazeiro) em relação às populações da região Centro Norte do Estado da Bahia, indicando um possível processo de isolamento reprodutivo / Abstract: Triatoma sherlocki, a specie first collected by Cerqueira, 1975, it is registered in the municipality of Gentio do Ouro region North Central from Bahia State, Brazil. Household population of T. sherlocki were found in a small artisan quarry-mining community in the municipality of Gentio do Ouro, known as Encantado. From the type locality (Santo Inácio) home invasions are common, but did not report any evidence of domestication, therefore information about its biology and epidemiology aspects in relation to the transmission of Chagas disease are needed. The main objective of this study was to determine if the genetic factor might be involved in the process of domestication of this specie and if the populations from anthropized environments could present genetic identity. Collected from wild strictly and anthropized environmental in the localities Santo Inácio and Encantado were performed between 2008 and 2009. The analysis of genetic variability of populations collected was verified by sequencing of fragment of the mitochondrial gene Cytochrome B and the genetic structure was evaluated by using analysis molecular variance (AMOVA). Specimens of the T. sherlocki were collected in nine locations, two anthropogenics, denominated "Encantado 1" and "Santo Inácio 1", and the others wild strictly denominated "Encantado 2", "Santo Inácio 2", "Gentio do Ouro 1", "Gentio do Ouro 2", "Gentio do Ouro 3", "Gentio do Ouro 4" and "Gentio do Ouro 5". Only in the Encantado 1 locality were collected nymphs and adults in households. In Santo Inácio 1 according the Health Secretary from Gentio do Ouro, Bahia, sporadic invasions are frequent and only adults were collected in households. 292 sequences of 565 bases pairs of the fragment mitochondrial gene Cyt B were obtained and 63 haplotypes were founded. Haplotype diversity values ranged from 0.602 in the "Gentio do Ouro 4" locality to 0.820 in the "Gentio do Ouro 2" locality. The results of AMOVA showed that the population grouping based on geographical distance resulted in a greater variation between groups (11.13%) than among populations within groups (2.83%). When performed the analysis based on groupings ecologic, ie, localities wild strictly vs. anthropized localities, where specimens household are observed, there was no significance for the variation between groups, which showed 13.39% of variation among populations within groups. These results rule out the hypothesis of passive spread to formation of household colonies in Encantado 1 from Santo Inácio 1, suggesting that colonizations of houses in Encantado 1 occurs from adjacent foci wild. As the populations Encantado 1 and 2 presented relative degree of genetic differentiation when compared to other populations, the possibility that the genetic factor is involved in the colonization of houses in Encantado should be considered. Analysis of populations of T. juazeirensis and T. melanica, others members of the Triatoma brasiliensis complex that occur in the Bahia State, was also conducted with the same approach for the inferences about the genetic structure of T. sherlocki. The variation between T. sherlocki and T. melanica populations are consistent with intraspecific differentiation, whereas T. juazeirensis found a high genetic differentiation between populations from the Type Locality (Juazeiro) in relation to the populations of the North Central region of Bahia State, indicating a possible process of reproductive isolation / Doutorado / Parasitologia / Doutor em Parasitologia

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