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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.
11

Genetic analysis of European beech populations across precipitation gradients: understanding the adaptive potential to climate change

Cuervo Alarcon, Laura Carolina 16 March 2017 (has links)
No description available.
12

A candidate gene-based association study to investigate potentially adaptive genetic variation in European beech (Fagus sylvatica L.) / Eine Kandidatengen-basierte Assoziationsstudie zur Untersuchung potentiell adaptiver genetischer Variation bei der Rotbuche (Fagus sylvatica L.)

Müller, Markus 19 December 2013 (has links)
Klimawandelmodelle sagen für Deutschland sowohl höhere Jahresdurchschnittstemperaturen als auch eine Abnahme von Niederschlägen in den Sommermonaten voraus. Mögliche Konsequenzen für Bäume sind eine verlängerte Vegetationsperiode, ein erhöhtes Spätfrostrisiko und mehr Trockenstress während des Sommers. Diese veränderten Umweltbedingungen könnten zu Veränderungen der Konkurrenzverhältnisse zwischen Baumarten führen. Die Rotbuche (Fagus sylvatica L.) ist eine der wichtigsten Laubbaumarten Mitteleuropas. Daher ist das genetische Anpassungspotential dieser Baumart an den Klimawandel von großem Interesse. In dieser Studie wurden sowohl die neutrale als auch die adaptive genetische Variation der Buche untersucht. Dafür wurde ein Translokationsexperiment mit Nachkommen von Buchenpopulationen, die unter verschiedenen Umweltbedingungen in Norddeutschland wachsen, etabliert. Wiederholte Aufnahmen wichtiger phänotypischer Merkmale (Höhe, Austrieb, Trockenstresssensitivität, Sterblichkeit) zeigten signifikante Unterschiede zwischen den Populationen. Interessanterweise zeigten Populationen mit einer größeren geographischen Distanz teilweise ähnlichere Phänotypen als benachbarte Populationen. Die neutrale genetische Variation der untersuchten Sämlingspopulationen wurde anhand neun verschiedener Mikrosatellitenmarker analysiert. Zwischen den analysierten Buchenpopulationen wurde nur eine geringe genetische Differenzierung ermittelt. Die genetische Diversität war hoch und statistisch nicht signifikant unterschiedlich von den Altbeständen, aus denen sie stammten. Die hohe genetische Diversität ist eine gute Basis für Adaption, allerdings könnte sie wahrscheinlich nur eine kurzfristige Anpassung an den Klimawandel ermöglichen. Daher ist es wichtig, Einblicke in die genetische Basis von klimawandelrelevanten Merkmalen zu gewinnen. Deshalb wurden in dieser Studie Kandidatengene für das Austriebsverhalten untersucht. Bei der Analyse von Fragmenten von zehn verschiedenen Kandidatengenen wurden 20 Indels und 116 SNPs identifiziert. Insgesamt wurden 46 SNPs erfolgreich zur Genotypisierung von über 1.400 Individuen, die aufgrund ihres Austriebsverhaltens ausgewählt wurden, verwendet. Assoziationsanalysen wurden durchgeführt, um potentiell adaptive SNP-Marker zu identifizieren. Diese ergaben unter einem „generalisierten linearen Modell“ 23 signifikant mit dem Austrieb assoziierte SNPs. Ein zusätzlich verwendetes „gemischtes lineares Modell“ ergab nahezu gleiche Ergebnisse. Die phänotypische Variation, die durch signifikant mit dem Austrieb assoziierte SNPs erklärt wird, war niedrig (R2 < 2,2), aber in Übereinstimmung mit anderen Studien mit Waldbaumarten. Zusätzlich zu den Assoziationsanalysen wurden auch FST-Outlier-Analysen durchgeführt. Diese ergaben sieben verschiedene SNPs, die potentiell unter ausgleichender oder gerichteter Selektion stehen. Insgesamt wurden vier potentiell adaptive SNPs gleichzeitig durch Assoziations- und Outlier-Analysen identifiziert. Diese könnten die höchste Wahrscheinlichkeit aufweisen, an der Ausprägung des Austriebsverhaltens beteiligt zu sein. Allerdings sind viele potentiell adaptive SNPs, die in dieser Studie identifiziert wurden, nicht-kodierend oder synonym und somit nicht die kausativen SNPs, sondern eher gelinkt mit ihnen. Allerdings wurde in dieser Studie ein geringes Kopplungsungleichgewicht (linkage disequilibrium) gefunden. Somit könnten die kausativen SNPs in naher Umgebung liegen. Die in dieser Studie identifizierten potentiell adaptiven SNPs sollten in weiteren Studien mit zusätzlichen Populationen bestätigt werden.
13

Assessment of genetic markers for the improvement of beef quality and consistency

Gill, Jennifer January 2010 (has links)
The overall aim of this thesis was to investigate the genetic control of beef quality in a commercial population of Aberdeen Angus-sired cattle with a view to trait improvement. The population studied included 500 Angus-cross animals, all with purebred Aberdeen Angus sires, from a selection of farms throughout Scotland. A number of carcass-related weight traits and taste panel assessed sensory traits were measured on these animals. A population of 265 Charolais cross cattle (all with purebred sires) was then used to explore the extrapolation of results across breeds. The first aim of this thesis was to investigate heritabilities for important carcass and meat quality traits and to assess the quality of a number of taste-panel derived meat quality traits by calculating three consistency statistics. Consistency statistics (parameter range 0 to 1) for the taste panel traits were moderately high, particularly for panel member consistency and reproducibility, with values ranging from 0.48 to 0.81 and 0.43 to 0.73, respectively. Estimated heritabilities were low for most of the sensory taste-panel-evaluated traits, where the maximum value was 0.16 for overall liking, but were higher for carcass traits where carcass weight heritability was 0.7. To perform these analyses it was first necessary to confirm paternity using a number of genetic markers. Therefore, a comparison of the power of both microsatellite and SNP markers for paternity exclusion was carried out to determine the more effective method. Results indicated that approximately three times as many SNP markers than microsatellite markers were required for parentage exclusion, and a panel of 15 microsatellite markers was used to assign paternity before subsequent data analysis was carried out. The remaining aims of this thesis centred on exploring genetic markers for carcass and meat quality. Firstly, the Angus animals were genotyped for the del11 myostatin mutation which was found to be segregating at a relatively low frequency (0.04) and was shown to be associated with a 17.4 kg increase in carcass weight (P < 0.05) in the heterozygous animals when compared to the homozygous wild-type animals. By analysing the haplotype associated with the mutant allele, it was determined that there have been at least two separate introductions of the mutant allele into the Aberdeen Angus breed. A number of SNPs were also tested for their effects on the carcass and meat quality traits in the Angus animals. The SNPs fell into two groups: eight that have been incorporated into commercially available tests and a further 28 from alternative candidate genes that have effects in different breeds and species. In total, 17 SNPs significantly affected at least one of the traits measured. Of these significant associations, a number have been seen previously, such as the association between calpain and tenderness (P = 0.01) and growth hormone and eye muscle area (P = 0.05), and some of which were novel, such as the association between growth hormone receptor and steak odour (P = 0.02) and corticotrophin releasing hormone and gristle distance from fat (P = 0.004). A further six SNPs, identified by resequencing of the malic enzyme 1 (ME1) and small heterodimer partner (SHP) genes, were tested for their effects on the traits measured in this thesis. Five of the SNPs, including one which caused a non-synonymous amino acid change, had a significant effect on at least one of the traits tested including fat class (P = 0.002), eye muscle area (P = 0.01), sirloin weight before maturation (P = 0.03), sirloin steak tail length (P = 0.004) and juiciness (P = 0.004) where the effect sizes were 1.79 units, 565 mm2, 0.36 kg, 17.12 mm and 0.23 taste panel units, respectively. To assess the effect of the genotyped SNPs on intramuscular fat (IMF), a simple method of visible IMF quantification in the sirloin steak was developed using digital photographs and an image analysis program. Results showed that two SNPs in the calpain gene, known to be linked with an increase in meat tenderness, were associated with an increase in visible IMF% and the del11 mutation was associated with a reduction in visible IMF%. The heritabilities, SNP association validations and novel SNP-trait associations identified in this thesis provide tools for use in breeding programs, possibly via marker assisted selection to improve meat quality traits. However, the results seem breed-specific, as most of the significant effects were not replicated in the Charolais population.
14

Analyse physiologique et génétique combinées pour améliorer le contenu en huile et la qualité du tournesol soumis à la sécheresse / Physiological and genetic analysis to improve quality and quantity of sunflower seed oil under drought stress

Haddadi, Parham 12 July 2010 (has links)
Le tocophérol, le phytostérol, le pourcentage de protéines des graines, l'huile et les teneurs en acides gras ont été mesurés dans une population de lignées recombinantes (RILS) de tournesol, cultivées sous conditions de sécheresse, irrigation et semis tardif. Une analyse génétique de QTL a été réalisée à partir de ces mesures, en utilisant une carte génétique basée sur des marques SSR et avec des gènes candidats (1) impliqués dans la voie métabolique de tocophérol et phytostérol, (2) des gènes codant des antioxydants enzymatiques, (3) des gènes liés à la sécheresse et (4) des gènes homologues à SEC14 chez Arabidopsis. Trois gènes candidats importants (VTE4, VTE2 et HPPD), qui codent pour des enzymes impliquées dans la biosynthèse du tocophérol, ont été cartographiés sur les groupes de liaison LG8 et LG14. Quatre SNPs sont identifiés pour PAT2, le gène homologue chez Arabidopsis SEC14, entre les deux parents (PAC2 et RHA266) et un SNP, identifié par alignement de séquences est converti en marqueur CAPS pour permettre l'analyse génotypique des RIL. Les gènes homologues à SFH3, HPPD, CAT et CYP51G1 ont été cartographiés grâce à la mise au point de marqueurs dominants, tandis que des marqueurs co-dominants ont permis la cartographie des gènes homologues à SEC14-1, VTE4, DROU1, POD, SEC14-2 et AQUA. Les gènes POD, CAT et GST, codant pour des antioxydants enzymatiques, ont également été cartographiés sur les groupes de liaison 17, 8 et 1, respectivement. Le QTL majeur pour la teneur en tocophérol a été identifié sur le groupe de liaison 8, qui explique 59,5% de la variation phénotypique (6.TTC.8). Il colocalsie également avec le QTL identifié pour la teneur en phytostérol (7.TPC.8). Sous condition de semis tardif, un QTL spécifique de la teneur en acide palmitique a été identifié sur le groupe de liaison 6 (PAC-LS.6). Il est situé entre les marqueurs ORS1233 et SSL66_1. Les QTLs pour le pourcentage d'huile de graines et la teneur en acide stéarique colocalisent sur les groupes de liaison 10 (PSO-PI.10 et SAC-WI.10) et 15 (PSO-PI.15 et SAC-LS.15). Sept QTLs associés à teneur en acides palmitique, stéarique, oléique et linoléique sont identifiés sur le groupe de liaison 14. Ils sont liés à l’homologue du gène HPPD. Par ailleurs, les caractères agronomiques tels que les jours du semis à la floraison, la hauteur des plantes, le rendement et la morphologie foliaire ont été étudiés. Des analyses association génétique ont permis d’identifier des QTLs intérêts sur les groupes de liaison 2, 10 et 13 pour les caractères étudiés, d’autres QTLs identifies sur les groupes de liaison 9 et 12 mettent en avant l'importance de ces régions génomiques pour les caractères de morphologie foliaire. Nous avons finalement identifié des marqueurs AFLP et quelques gènes candidats liés aux caractères impliqués dans la qualité des graines sous conditions irriguée et stress hydrique chez une population de mutants (M8). Deux lignées mutantes, M8-826-2-1 et M8-39-2-1, produisent un niveau significativement élevé d'acide oléique peuvent être utilisées dans les programmes de sélection en raison de la haute stabilité à l'oxydation et des propriétés cardiovasculaire apportés par l’acide oléique qu’elles produisent. L'augmentation du niveau de tocophérol dans les lignées mutantes, M8-862-1N1 et M8-641-2-1, est justifiée par le polymorphisme observé pour le gène, MCT, impliqué dans la voie métabolique du tocophérol. Le marqueur le plus important pour le contenu en tocophérol total est E33M50_16 qui explique 33,9% de la variation phénotypique. Un des gènes candidats les plus importants concernant la biosynthèse des acides gras, FAD2 (FAD2-1), est lié à la teneur en acides oléique et linoléique. Il explique plus de 52% de la variation phénotypique. / The genetic control of tocopherol, phytosterol, percentage of seed protein, oil and fatty acids content in a population of recombinant inbred lines (RILs) of sunflower under various conditions are studied through QTL analysis using genetic-linkage map based on SSR markers and introducing some important tocopherol and phytosterol pathway-related genes, enzymatic antioxidant-related genes, droughtresponsive family genes and Arabidopsis SEC14 homologue genes. Three important candidate genes (HPPD, VTE2 and VTE4), which encode enzymes involved in tocopherol biosynthesis, are mapped to linkage group 8(LG8) and LG14. One of the most important candidate genes coding for sterol methyltransferase II (SMT2) enzyme is anchored to LG17 by CAPS marker. Four SNPs are identified for PAT2, Arabidopsis Sec14 homologue gene, between two parents (PAC2 and RHA266). PAT2 is assigned to LG2 by CAPS marker. Squalene epoxidase (SQE1) is also assigned to LG15 by InDel marker. Through other candidate genes, POD, CAT and GST encoding enzymatic antioxidants are assigned to LG17, LG8 and LG1, respectively. The major QTL for total tocopherol content on linkage group 8 accounted for 59.5% of the phenotypic variation (6.TTC.8), which is overlapped with the QTL of total phytosterol content (7.TPC.8). Under late-sowing condition, a specific QTL of palmitic acid content on linkage group 6 (PAC-LS.6) is located between ORS1233 and SSL66_1 markers. Common chromosomic regions are observed for percentage of seed oil and stearic acid content on linkage group 10 (PSO-PI.10 and SACWI. 10) and 15 (PSO-PI.15 and SAC-LS.15). Overlapping occurs for QTLs of oleic and linoleic acids content on linkage groups 10, 11 and 16. Seven QTLs associated with palmitic, stearic, oleic and linoleic acids content are identified on linkage group 14. These common QTLs are linked to HPPD homologue, HuCL04260C001. QTLs controlling various traits such as days from sowing to flowering, plant height, yield and leaf-related traits are also identified under well-, partial-irrigated and late-sowing conditions in a population of recombinant inbred lines (RILs). The results do emphasis the importance of the role of linkage group 2, 10 and 13 for studied traits. Genomic regions on the linkage group 9 and 12 are important for QTLs of leaf-related traits in sunflower. We finally identified AFLP markers and some candidate genes linked to seed-quality traits under well-irrigated and water-stressed conditions in gammainduced mutants of sunflower. Two mutant lines, M8-826-2-1 and M8-39-2-1, with significant increased level of oleic acid can be used in breeding programs because of their high oxidative stability and hearthealthy properties. The significant increased level of tocopherol in mutant lines, M8-862-1N1 and M8- 641-2-1, is justified by observed polymorphism for tocopherol pathway-related gene; MCT. The most important marker for total tocopherol content is E33M50_16 which explains 33.9% of phenotypic variance. One of the most important candidate genes involving fatty acid biosynthesis, FAD2 (FAD2-1), is linked to oleic and linoleic acids content and explained more than 52% of phenotypic variance.
15

Genetic response of tree population to spatial climatic variation : an experimental genomic and simulation approach in Fagus sylvatica populations along altitudinal gradients / Réponse génétique d'une population d'arbre à une variation dans l'espace du climat : une approche de génomique expérimentale et de simulations sur différents gradients altitudinaux chez Fagus sylvatica

Lalagüe, Hadrien 14 March 2013 (has links)
Un enjeu majeur de la génétique évolutive est de comprendre comment l'adaptation locale se développe en population naturelle, et comment les différentes forces évolutives y contribuent. Les études expérimentales d'adaptation locale utilisent couramment les gradients altitudinaux présentant une variation spatiale marquée des conditions environnementales. Dans ces conditions, on s'attend à ce que la différentiation génétique pour les caractères (traditionnellement mesurée par QST) et pour les gènes déterminant ces caractères (traditionnellement mesurée par FSTq) le long du gradient soit gouvernée de façon prédominante par la sélection et les flux de gènes, et peu influencée en revanche par la dérive génétique et la mutation. En particulier, des études théoriques ont montré un découplage entre QST et FST lorsque que les flux de gènes sont forts et/ou que la sélection est récente. Dans cette étude, nous avons testé cette hypothèse en combinant une approche de génomique expérimentale et des simulations dans des populations naturelles de hêtre commun (F. sylvatica) séparées de ~trois kilomètres et soumis à des environnements contrastés.Pour l'approche expérimentale, nous avons échantillonné 4 populations sur deux gradients altitudinaux sur le Mont Ventoux (avec une population à haute altitude et une à basse altitude sur chaque gradient). Cinquante huit gènes potentiellement impliqué dans la réponse aux stress abiotiques et dans le débourrement ont été séquencés sur un total de quatre-vingt seize individus, révélant 581 SNPs (Single Nucleotide Polymorphisms). Différentes approches ont été utilisées pour identifier les SNP outlier, présentant une différentiation plus forte qu'attendu sous un modèle neutre sans sélection. Le nombre de SNPs outlier identifié comme étant sous sélection s'est révélé être grandement dépendant de la méthode utilisé. La méthode fréquentiste a détecté de nombreux outliers alors que l'approche bayésienne n'a pu permettre de détecter des SNPs sous sélection. Par ailleurs, nous avons utilisé un modèle mécaniste individu-centré pour simuler les patrons de diversité phénotypique et génétique attendus le long du gradient pour la phénologie du débourrement végétatif, un caractère généralement adaptatif dans la réponse aux variations de température. Les résultats des simulations confirment que la différentiation génétique observée pour le caractère (QST) est généralement plus forte que celle observée au gène (FSTq), et que cette différentiation génétique au trait intervient dès la première génération. Toutefois, les tests d'outlier conduits sur le le modèle simulé ont révélé que plus de 95% des SNPs outlier sont des faux positifs. Comme dans l'approche expérimentale, l'approche Bayésienne ne s'est pas révélé suffisamment fiable pour détecter des QTLs dans des populations spatialement proche et génétiquement faiblement différentiée. Néanmoins une approche multi-locus basée sur un estimateur peu utilisé en génétique (le Zg) a révélé la forte corrélation inter-populations inter-gènes des QTLs confirmant les attendus théoriques. Toutefois, cette approche ne permet pas de détecter précisément les QTLs sans connaissance a priori sur les QTLs. En conclusion, les travaux de cette thèse mettent en évidence la rapidité des changements génétique qui interviennent en moins de 5 générations pendant la modification du climat, et la difficulté de détecter les gènes codant pour des traits complexes. / A major challenge in population genetics is to understand the local adaptation process in natural population and so to disentangle the various evolution forces contributing to local adaptation. The experimental studies on local adaption generally resort to altitudinal gradients that are characterized by strong environmental changes across short spatial scales. Under such condition, the genetic differentiation of the functional trait (measured by the Qst) as well as the genes coding for trait (measured by Fstq) are expected to be mainly driven by selection and gene flow. Genetic drift and mutation are expected to have minor effect. Theoretic studies showed a decoupling between Qst and Fst under strong gene flow and / or recent selection. In this study, I tested this hypothesis by combining experimental and modelling genomic approach in natural population of Fagus sylvatica separated by ~3 kilometres and under contrasted environments.Sampling was conducted in south-eastern France, a region known to have been recently colonised by F.sylvatica. Four naturally-originated populations were sampled at both high and low elevations along two altitudinal gradients. Populations along the altitudinal gradients are expected to be subjected to contrasting climatic conditions. Fifty eight candidate genes were chosen from a databank of 35,000 ESTs according to their putative functional roles in response to drought, cold stress and leaf phenology and sequenced for 96 individuals from four populations that revealed 581 SNPs. Classical tests of departure of site frequency spectra from expectation and outlier detection tests that accounted for the complex demographic history of the populations were used. In contrast with the mono-locus tests, an approach for detecting selection at the multi-locus scale have been tested.The results from experimental approaches were highly contrasted according the method highlighting the limits of those method for population loosely differentiated and spatially close. The modelling approach confirmed the results from the experimental data but revealed that up to 95% of the SNPs detected as outliers were false positive. The multi-locus approach revealed that the markers coding for the trait are differentially correlated compared to the neutral SNPs. But this approach failed to detect accurately the markers coding for the trait if no a priori knowledge is known about them. The modelling approach revealed that genetic changes may occur across very few generation. But while this genetic adaptation is measurable at the trait level, the available method for detecting genetic adaptation at the molecular level appeared to be greatly inaccurate. However, the multi-locus approach provided much more promise for understanding the genetic basis of local adaptation from standing genetic variation of forest trees in response to climate change.
16

Caracterização de rearranjos cromossômicos em pacientes com malformações congênitas múltiplas e/ou retardamento mental (MCA/MR) / Characterization of chromosome rearrangements in patients with multiple congenital malformation and/or mental retardation (MCM/MR)

Oliveira, Mariana Angelozzi de 05 May 2008 (has links)
As alterações cromossômicas estruturais associadas a fenótipos clínicos oferecem a oportunidade de identificação e localização de genes cujas mutações possam estar determinando essas patologias, tendo em vista a possibilidade de que esses genes podem ter sido alterados pelas quebras ou ter o número de cópias modificado. Um número cada vez maior de evidências aponta para a participação de certas seqüências do genoma na formação de rearranjos cromossômicos recorrentes e não recorrentes. Este trabalho compreendeu o estudo de duas translocações cromossômicas aparentemente equilibradas e uma duplicação do braço curto do cromossomo 20 em decorrência de mosaicismo materno. O objetivo foi determinar os pontos de quebra por hibridação in situ fluorescente (FISH) e identificar genes candidatos, alterados pelas quebras dos rearranjos e que pudessem explicar o quadro clínico dos portadores. A caracterização das seqüências nos pontos de quebra e a junção desses rearranjos é fundamental para a compreensão dos mecanismos de formação das alterações cromossômicas. A delimitação precisa dos segmentos deletados é necessária para a correlação com o quadro clínico. / Two apparently \"de novo\" balanced translocations and one duplication of the short arm of chromosome 20 were studied. Our aim was to determine the breakpoints by chromosomal analysis through fluorescentin situ hybridization (FISH) and identify candidate genes and how they were involved with the clinical phenotypes of the patients. Patient 1 carried a duplication of the short arm of chromosome 20 (p11.22p13), inherited from the mother that showed normal and dup(20) lymphocytes. The duplication was determined by FISH using BAC and PAC clones, and nine clones were duplicated except one (20p11.21). The patient shared many of the common characteristics of trisomy 20p including delay in motor development, hypertelorism, poor coordination, round face with prominent cheeks, vertebral and dental abnormalities and cranial asymmetry with high and large forehead. She also had learning difficulties, behavioral disorders and pubertal growth spurt at 12 years. As our patient is an example of pure trisomy 20p, the features are of particular importance to delineate the syndrome. Three genes were mapped on the segment that contain the duplication (20p11.2-13), one of these genes is the SSTR4 (Somatostatin receptor 4). The somatostatin is widely distributed throughout the body and is important regulator of endocrine and nervous system function. It is an inhibitor of growth hormone secretion. The second gene is the BMP2 that produce bone morphogenetic proteins and it has a direct function with the nervous system. The third gene is the GHRH that produce proteins connected with the growth hormone. These genes might have been over expressed and thus contributing to the patient\'s clinical features. Patient 2, carried a 46,XY,t(5;14)(q14.1;q31.3)de novo translocation. On chromosome 14 the breakpoint was mapped to a segment contained in BAC RP11-315O17 (14q31.3). On the chromosome 5 the breakpoint was mapped to a segment contained in BAC RP11-30D15 (5q14.1). Although the breakpoint, on the chromosome 14, has been mapped in 14q31.3, our patient shared many of the common characteristics of terminal 14q32 deletion: mental retardation, dolicocephaly, prominent ears, hypertelorism, strabismus, upturned palpebral fissures, highly arched palate, simian crease, severe myopia, coloboma and palpebral ptosis. As mental retardation and ocular abnormalities were the main patient\'s clinical features, we are suggesting that: 1) a region of segment 14q31.3 was deleted. 2) A gene inside this segment (14q31.3) could be responsible for ocular development and 3) a disrupted gene could interfere on the expression of other genes. On chromosome 5 eleven genes were localized and four of them are expressed in nervous system (AP3B1; SCAMP1; BHMT2 e CMYA5). One of these genes might have been disrupted and is contributing to the patient\'s clinical features. Patient 3 was the carrier of a 46,XY,t(1;15)(p13.2;q25.2)de novo translocation. The breakpoint on chromosome 15 was mapped to the segment contained in clone RP11-152F13 (15q25.2). The breakpoint on chromosome 1 was mapped to the segment contained in clone RP5-1037B23 (1p13.2). The genes mapped at the breakpoint regions of chromosome 1 and chromosome 15 are expressed in nervous system and muscles. Our patient shows few clinical features: speech delay, stutter and learning difficulties, probably because one or more of these genes, mapped at the breakpoint region, could be disrupted.
17

Polimorfismo do gene MSTN e do SNP BIEC2-808543 e sua rela??o com crescimento de potros da ra?a brasileiro de hipismo / Polymorphism of MSTN gene and SNP BEC2-808543 and its relation to growth of Brasileiro de Hipismo foals

Costa, ?rica Cristina Xisto da 31 July 2015 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-25T15:40:39Z No. of bitstreams: 1 2015 - ?rica Cristina Xisto da Costa.pdf: 2608729 bytes, checksum: a906abcd8f725dc6509fedcf8de9e08c (MD5) / Made available in DSpace on 2017-01-25T15:40:39Z (GMT). No. of bitstreams: 1 2015 - ?rica Cristina Xisto da Costa.pdf: 2608729 bytes, checksum: a906abcd8f725dc6509fedcf8de9e08c (MD5) Previous issue date: 2015-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The gene encoding myostatin (MSTN), located on chromosome 18 (ECA 18) and the SNP BIEC2-808543 located in the intergenic region, which precedes the gene encoding the protein similar to the nuclear corepressor receptor dependent binder (LCORL), located on chromosome 3 (ACE 3) in horses, both positioned in regions that are associated with conformational traits of these animals. In view of this, we aimed to identify if the variations described in MSTN and LCORL loci exist in the study population; and to identify the effects of these polymorphisms on the growth profiles of these animals. For this purpose, the characteristics measured were weight, height at withers and hip height of foals at different ages, belonging to the Coudelaria e Campo de Instru??o de Rinc?o do Ex?rcito Brasileiro. Nonlinear mixed models were adjusted resulting from the combination of six nonlinear simple models, Brody (1945), Gompertz (Winsor, 1932), Logistics (Ratkowski, 1983), Von Bertalanffy (1957), generalized Michaelis- Menten (Lopez et al., 2000) and Richards (1959) associated with four types of variance functions for each model, homogeneous, exponential, asymptotic and staggered. The polymorphism described in the promoter region of the MSTN gene was not found in the studied population, in which there has been only the T allele, however the BIEC2-808543 polymorphism, located in the region prior to the LCORL gene is significantly associated (P <0, 05) to the characteristics evaluated, in which the animals who presented the genotype TT were smaller and lighter when compared to the other genotypes. There was no significant difference between animals with CT and CC genotype. The model that best describes the growth curve for body mass variance is the model of Brody (1945) associated with the scaled variance for the variable height at the withers the model that best fit was the Von Bertalanffy (1957) (adjusted without polymorphism effect in b) parameter associated with the asymptotic variance and the characteristic hip height the model that best described was that of Brody (1945) associated with the asymptotic variance, explaining that the nonlinear mixed models are indeed promising to describe equine growth curves, for the simple models did not differ much among themselves what defined in fact the selection of the model was the variance, being for body mass staggered variance and the height at the withers and on the back, the asymptotic variance. This polymorphism can be used as molecular markers for early selection of foals as to the characteristics evaluated / O gene que codifica a miostatina (MSTN), localizado no cromossomo 18 (ECA 18) e o SNP BIEC2-808543 localizado na regi?o interg?nica que antecede o gene que codifica a prote?na semelhante a correpressor de receptor nuclear dependente de ligante (LCORL), localizado no cromossomo 3 (ECA 3) de cavalos, ambos posicionados em regi?es que est?o associadas ?s caracter?sticas conformacionais destes animais. Diante disto, objetivamos identificar se as varia??es descritas nos loci MSTN e LCORL, existem na popula??o em estudo; al?m de verificar os efeitos desses polimorfismos sobre os perfis de crescimento desses animais. Com este intuito foram mensuradas as caracter?sticas massa corporal, altura na cernelha e altura na garupa de potros em diversas faixas et?rias, pertencentes ? Coudelaria e Campo de Instru??o de Rinc?o do Ex?rcito Brasileiro. Foram ajustados modelos n?o lineares mistos que resultaram da combina??o de seis modelos n?o lineares simples, Brody (1945), Gompertz (Winsor, 1932), Log?stico (Ratkowski, 1983), Von Bertalanffy (1957), Michaelis-Menten generalizado (L?pez et al., 2000) e Richards (1959), associados a quatro tipos de fun??es de vari?ncia para cada modelo, homog?nea, exponencial, assint?tica e escalonada. O polimorfismo descrito na regi?o promotora do gene MSTN n?o foi encontrado na popula??o estudada, na qual observa-se apenas o alelo T, entretanto o polimorfismo BIEC2-808543, localizado na regi?o que antecede o gene LCORL, est? significativamente associado (P<0,05) ?s caracter?sticas avaliadas, sendo os animais que apresentaram o gen?tipo TT menores e mais leves quando comparado com os demais gen?tipos. N?o foi observada diferen?a significativa entre os animais com gen?tipo TC e CC. O modelo que melhor descreve a curva de crescimento para a vari?vel massa corporal ? o modelo de Brody (1945) associado com a vari?ncia escalonada, para a vari?vel altura na cernelha o modelo que melhor se ajustou foi o de Von Bertalanffy (1957) (ajustado sem efeito de polimorfismo no par?metro b) associado com a vari?ncia assint?tica e para a caracter?stica altura na garupa o modelo que melhor a descreveu foi o de Brody (1945) associado ? vari?ncia assint?tica, elucidando que os modelos n?o-lineares mistos s?o de fato promissores para a descri??o de curvas de crescimento de equinos, pois os modelos simples n?o diferiram muito entre si o que definiu de fato a sele??o do modelo foi a vari?ncia, sendo para massa corporal a vari?ncia escalonada e para as alturas, na cernelha e na garupa, a vari?ncia assint?tica. Este polimorfismo pode ser utilizado como marcador molecular para sele??o precoce de potros quanto ?s caracter?sticas avaliadas
18

Analysis of Specific Migraine Candidate Genes Mapping to Human Chromosome 1

Sundholm, James, n/a January 2003 (has links)
Migraine, comprised of migraine with aura (MA) and migraine without aura (MO), is a painful neurovascular disease, affecting approximately 16% of the general population. It is characterised by a wide variety of symptoms including headache, nausea and vomiting, and photo- and phonophobia. The disorder is complex involving not only multiple genes, but also specific environmental factors, which can induce attacks in genetically predisposed individuals. Hyperhomocysteinaemia is a known risk factor for cerebrovascular, peripheral vascular and coronary heart disease. The Methylenetetrahydrofolate Reductase (MTHFR) enzyme is involved in homocysteine metabolism. Furthermore, it has been reported that a homozygous mutation (677C to T; Ala to Val) in the 5,10-MTHFR gene is associated with an elevation in plasma homocysteine levels (Frosst et al., 1995). This common mutation in the MTHFR gene has recently been associated with migraine with aura in a Japanese cohort (Kowa et al., 2000). The present study was designed to determine the prevalence of the MTHFR C677T mutation in Australian patients with migraine and to determine whether this mutation is associated with the disease in Caucasians. A large case-control study, consisting of 270 patients with migraine (167 with aura and 103 without aura), and 270 normal matched controls was investigated. Genotypic results indicated that the prevalence of the homozygous (T/T) genotype in migraine sufferers (15%) was higher than that of controls (9%) (P = 0.084). Furthermore, the frequency of the mutant (T/T) genotype in individuals with MA (19%) was significantly higher than in controls (9%) (P = 0.006). Interestingly, the risk of MA was ~2.5-fold higher in suffers possessing the homozygous variant (OR = 2.52, CI: 1.42 - 4.47, P = 0.0012). To confirm the MTHFR allelic association with MA, family-based tests were performed in an independent pedigrees group, where only those with MA were considered affected. Results from both the Pedigree Disequilibrium Test (PDT) and Family-Based Association Test (FBAT) analysis revealed slight, although not significant (PDT test, P = 132; and FBAT test, P = 0.390), over-transmission of the mutant allele (T) from parents to affected offspring. However, despite the MTHFR variant having a high heterozygosity (0.48), there were a limited number of informative transmissions for the MTHFR variant in the pedigree group resulting in reduced power for these tests. In conclusion, our results support the trends reported in the Japanese migraine study and suggest that the homozygous 677T gene variant causing mild hyperhomocysteinaemia, is a genetic risk factor for migraine, and indicate that further studies investigating the role of this gene are warranted. Mutations in various ion channel genes are responsible for neurovascular and other neurological disorders. Inherited ion channel mutations or "channelopathies" are increasingly found to be the cause of various neurological disorders in humans. Wittekindt and colleagues (1998) reported that the calcium-activated potassium channel (hKCa3) gene is a good candidate for schizophrenia and bipolar disorder (BD), as well as for other neurological disorders such as migraine. The hKCa3 gene is a neuronal small conductance calcium-activated potassium channel, which contains a polyglutamine tract, encoded by a polymorphic CAG repeat in the gene. The hKCa3 gene encodes a protein of 731 amino acids containing two adjacent polyglutamine sequences in its N-terminal domain separated by 25 amino acids. The C-terminal polyglutamine sequence is highly polymorphic in length (Austin et al., 1999). hKCa3 plays a critical role in determining the firing pattern of neurons via the generation of slow after-polarization pulses and the regulation of intracellular calcium channels (Kohler et al., 1996). Three distinct mutations in the a1 calcium channel gene have been shown to cause SCA-6, episodic ataxia-2 and familial hemiplegic migraine (FHM) (Ophoff et al., 1996). The hKCa3 gene contains a highly polymorphic CAG repeat that was initially mapped (Chandy et al., 1997) to a schizophrenia locus on chromosome 22 (Pulver et al., 1994). Recently Austin et al (1999) re-mapped hKCa3 and found it to reside on chromosome 1q21, a region that has been linked to FHM (Austin et al., 1999), a rare subtype of MA (Ducros et al., 1997; Gardner et al., 1998), and a region recently showing genetic linkage to typical migraine (Lea et al., 2002). The hKCa3 polymorphism results in small variations in polyglutamine number, similar to those that occur in the calcium channel a1a subunit gene (CACNA1A), which is encoded by CAG expansions and thought to cause Spinocerebellar Ataxia Type 6 via loss of channel function (Austin et al., 1999). Given the recent linkage of FHM to the region of chromosome 1q21, to which hKCa3 resides, and also linkage of typical migraine to this region, a large case-control study investigating this hKCa3 CAG marker and consisting of 270 migraine and 270 stringently matched healthy controls was undertaken. Our results indicated that there was no statistically significant difference in allele distributions for this marker between migraine and non-migraine patients (P >0.05). No significant difference in the allelic distribution was observed in the MA or MO groups when compared to controls (P >0.05) and there was no significant difference in CAG repeat length distribution between the migraine group and controls (P = 0.92), or between the MA and MO groups (P = 0.72) collectively. Hence, the CAG repeat in this gene does not show expansion in migraine. Overall, our results provide no genetic evidence to suggest that the hKCa3 CAG repeat polymorphism is involved in migraine aetiology in Australian Caucasians. Thus the involvement of the hKCa3 gene in migraine is not likely, although the hKCa3 gene remains an important candidate for other neurological disorders that may be linked to the 1q21.3 chromosomal region.
19

Caracterização da variabilidade de genes relacionados ao desenvolvimento muscular, fertilidade e temperamento em equinos da raça mangalarga /

Arneiro, Lidia Carolina Meira. January 2011 (has links)
Resumo: Em mamíferos, incluindo os eqüinos (Equus caballus), o gene protein kinase, AMP-activated, gamma 3 non-catalytic subunit (PRKAG3) encontra-se relacionado ao desempenho muscular, os genes cysteine-rich secretory protein 1 (CRISP1) e spermatogenesis associated 1 (SPATA1) à fertilidade de machos e os genes 5-hydroxytryptamine (serotonin) receptor 1A (HTR1A) e solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) ao temperamento. Os objetivos deste trabalho foram a padronização de metodologia alternativa de genotipagem por PCR-RFLP dos SNPs AY_376689:c.773C>T, AJ_315378:c.110A>G e AB_264325:c.771G>C dos genes eqüinos PRKAG3, CRISP1 e HTR1A, respectivamente, bem como a caracterização em cavalos da raça brasileira Mangalarga destes e de outros polimorfismos, o AAWR_02017454:g.121684T>C do gene SPATA1 e o AB_098561:c.1470G>A do gene SLC6A4, a fim de promover o embasamento necessário para futuras pesquisas visando associação entre marcadores de DNA e características de interesse na raça. Foram utilizados 151 animais Mangalarga, de ambos os sexos e de idades variadas, representativos da população do Estado de São Paulo. O método de PCR-RFLP mostrou-se adequado para a genotipagem dos SNPs AY_376689:c.773C>T do PRKAG3, AJ_315378:c.110A>G do CRISP1 e AB_264325:c.771G>C do HTR1A. Entretanto, os polimorfismos do PRKAG3 e CRISP1 provavelmente não ocorrem na Mangalarga, impossibilitando estudos de associação com os marcadores. As estimativas dos parâmetros genético-populacionais obtidas para o polimorfismo AAWR_02017454:g.121684T>C do gene SPATA1 na amostra estudada demonstraram a possibilidade de realização de pesquisas visando a sua associação com fertilidade de machos. As mesmas estimativas obtidas para os polimorfismos AB_264325:c.771G>C do HTR1A e o AB_098561:c.1470G>A do SLC6A4 desencorajam a realização de pesquisas visando suas associações à características relacionadas ao temperamento / Abstract: In mammals, including the equine (Equus caballus), the protein kinase, AMP-activated, gamma 3 non-catalytic subunit (PRKAG3) gene is related to muscular development, the cysteine-rich secretory protein 1 (CRISP1) and spermatogenesis associated 1 (SPATA1) genes are related to male fertility and the 5-hydroxytryptamine (serotonin) receptor 1A (HTR1A) and solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) genes are related to temperament. The aims of the present study were to propose an alternative genotyping method for the AY_376689:c.773C>T, AJ_315378:c.110A>G and AB_264325:c.771G>C SNPs of the equine PRKAG3, CRISP1 and HTR1A genes, respectively, as well as the characterization in Mangalarga Brazilian breed horses of these and other polymorphisms, the AAWR_02017454:g.121684T>C of the SPATA1 gene and the AB_098561:c.1470G>A of the SLC6A4 gene, in order to provide the necessary basis for future research towards associating the DNA markers and traits of interest in this breed. For this, 151 Mangalarga animals were used, from both sexes and random ages, representing the São Paulo state population. The PCR-RFLP methodology was found to be adequate for the genotyping of the SNPs AY_376689:c.773C>T of the PRKAG3, AJ_315378:c.110A>G of the CRISP1 and AB_264325:c.771G>C of the HTR1A. Nevertheless, the PRKAG3 and CRISP1 polymorphisms probably do not occur in Mangalarga, making it impossible the association studies with these markers. The estimative of the population genetic parameters obtained for the AAWR_02017454:g.121684T>C polimorphism of the SPATA1 gene in the sample studied showed the possibility of carrying out research towards its association with male fertility. On the other hand, the same estimatives obtained for the polymorphisms AB_264325:c.771G>C of the HTR1A and AB_098561:c.1470G>A of the SLC6A4 discourage research towards their association to traits related to temperament / Orientador: Marcílio Dias Silveira da Mota / Coorientador: Rogério Abdallah Curi / Banca: Humberto Tonhati / Banca: Evaldo Antonio Lencioni Titto / Mestre
20

Caracterização da variabilidade de genes relacionados ao desenvolvimento muscular, fertilidade e temperamento em equinos da raça mangalarga

Arneiro, Lidia Carolina Meira [UNESP] 18 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-18Bitstream added on 2014-06-13T18:54:03Z : No. of bitstreams: 1 arneiro_lcm_me_jabo.pdf: 935977 bytes, checksum: a8cbfbbed53f54f73a608f20e432bfe4 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Em mamíferos, incluindo os eqüinos (Equus caballus), o gene protein kinase, AMP-activated, gamma 3 non-catalytic subunit (PRKAG3) encontra-se relacionado ao desempenho muscular, os genes cysteine-rich secretory protein 1 (CRISP1) e spermatogenesis associated 1 (SPATA1) à fertilidade de machos e os genes 5-hydroxytryptamine (serotonin) receptor 1A (HTR1A) e solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) ao temperamento. Os objetivos deste trabalho foram a padronização de metodologia alternativa de genotipagem por PCR-RFLP dos SNPs AY_376689:c.773C>T, AJ_315378:c.110A>G e AB_264325:c.771G>C dos genes eqüinos PRKAG3, CRISP1 e HTR1A, respectivamente, bem como a caracterização em cavalos da raça brasileira Mangalarga destes e de outros polimorfismos, o AAWR_02017454:g.121684T>C do gene SPATA1 e o AB_098561:c.1470G>A do gene SLC6A4, a fim de promover o embasamento necessário para futuras pesquisas visando associação entre marcadores de DNA e características de interesse na raça. Foram utilizados 151 animais Mangalarga, de ambos os sexos e de idades variadas, representativos da população do Estado de São Paulo. O método de PCR-RFLP mostrou-se adequado para a genotipagem dos SNPs AY_376689:c.773C>T do PRKAG3, AJ_315378:c.110A>G do CRISP1 e AB_264325:c.771G>C do HTR1A. Entretanto, os polimorfismos do PRKAG3 e CRISP1 provavelmente não ocorrem na Mangalarga, impossibilitando estudos de associação com os marcadores. As estimativas dos parâmetros genético-populacionais obtidas para o polimorfismo AAWR_02017454:g.121684T>C do gene SPATA1 na amostra estudada demonstraram a possibilidade de realização de pesquisas visando a sua associação com fertilidade de machos. As mesmas estimativas obtidas para os polimorfismos AB_264325:c.771G>C do HTR1A e o AB_098561:c.1470G>A do SLC6A4 desencorajam a realização de pesquisas visando suas associações à características relacionadas ao temperamento / In mammals, including the equine (Equus caballus), the protein kinase, AMP-activated, gamma 3 non-catalytic subunit (PRKAG3) gene is related to muscular development, the cysteine-rich secretory protein 1 (CRISP1) and spermatogenesis associated 1 (SPATA1) genes are related to male fertility and the 5-hydroxytryptamine (serotonin) receptor 1A (HTR1A) and solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) genes are related to temperament. The aims of the present study were to propose an alternative genotyping method for the AY_376689:c.773C>T, AJ_315378:c.110A>G and AB_264325:c.771G>C SNPs of the equine PRKAG3, CRISP1 and HTR1A genes, respectively, as well as the characterization in Mangalarga Brazilian breed horses of these and other polymorphisms, the AAWR_02017454:g.121684T>C of the SPATA1 gene and the AB_098561:c.1470G>A of the SLC6A4 gene, in order to provide the necessary basis for future research towards associating the DNA markers and traits of interest in this breed. For this, 151 Mangalarga animals were used, from both sexes and random ages, representing the São Paulo state population. The PCR-RFLP methodology was found to be adequate for the genotyping of the SNPs AY_376689:c.773C>T of the PRKAG3, AJ_315378:c.110A>G of the CRISP1 and AB_264325:c.771G>C of the HTR1A. Nevertheless, the PRKAG3 and CRISP1 polymorphisms probably do not occur in Mangalarga, making it impossible the association studies with these markers. The estimative of the population genetic parameters obtained for the AAWR_02017454:g.121684T>C polimorphism of the SPATA1 gene in the sample studied showed the possibility of carrying out research towards its association with male fertility. On the other hand, the same estimatives obtained for the polymorphisms AB_264325:c.771G>C of the HTR1A and AB_098561:c.1470G>A of the SLC6A4 discourage research towards their association to traits related to temperament

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