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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.
131

The genetics of atrial septal defect and patent foramen ovale

Kirk, Edwin Philip Enfield, Women's & Children's Health, Faculty of Medicine, UNSW January 2007 (has links)
Congenital heart disease is the most common form of birth defect, affecting approximately 1% of liveborn babies. Secundum atrial septal defect (ASD) is the second most common form of congenital heart disease (CHD). Most cases have no known cause. Chromosomal, syndromal and teratogenic causes account for a minority of cases. The hypothesis that mutations in the ASD genes NKX2-5 and GATA4 may cause apparently sporadic ASD was tested by sequencing them in unrelated probands with ASD. In this study, 1/102 individuals with ASD had an NKX2-5 mutation, and 1/129 had a deletion of the GATA4 gene. The cardiac transcription factor TBX20 interacts with other ASD genes but had not previously been associated with human disease. Of 352 individuals with CHD, including 175 with ASD, 2 individuals, each with a family history of CHD, had pathogenic mutations in TBX20. Phenotypes included ASD, VSD, valvular abnormalities and dilated cardiomyopathy. These studies of NKX2-5, GATA4 and TBX20 indicate that dominant ASD genes account for a small minority of cases of ASD, and emphasize the considerable genetic heterogeneity in dominant ASD (also caused by mutations in MYH6 and ACTC). A new syndrome of dominant ASD and the Marcus Gunn jaw winking phenomenon is reported. Linkage to known loci was excluded, extending this heterogeneity, but a whole genome scan did not identify a candidate locus for this disorder. Previous studies of inbred laboratory mice showed an association between patent foramen ovale (PFO) and measures of atrial septal morphology, particularly septum primum length (???flap valve length??? or FVL). In humans, PFO is associated with cryptogenic stroke and migraine, and is regarded as being in a pathological contiuum with ASD. Twelve inbred strains, including 129T2/SvEms and QSi5, were studied, with generation of [129T2/SvEms x QSi5] F1, F2 and F14 mice. Studies of atrial morphology in 3017 mice confirmed the relationship between FVL and PFO but revealed considerable complexity. An F2 mapping study identified 7 significant and 6 suggestive quantitative trait loci (QTL), affecting FVL and two other traits, foramen ovale width (FOW) and crescent width (CRW). Binary analysis of PFO supported four of these.
132

AB-QTL analysis for two populations of winter barley sharing the donor of Hordeum vulgare ssp.spontaneum

Wang, Huajun. Unknown Date (has links) (PDF)
University, Diss., 2005--Bonn.
133

Mapeamento de locos associados ao conteúdo de proteínas de reserva em soja / Mapping loci associated with storage protein content of soybeans

Soares, Taís Cristina Bastos 24 March 2004 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-10-05T19:01:16Z No. of bitstreams: 1 texto completo.pdf: 1450755 bytes, checksum: 7b05d5c67d98257fd3c5469f873df50a (MD5) / Made available in DSpace on 2016-10-05T19:01:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1450755 bytes, checksum: 7b05d5c67d98257fd3c5469f873df50a (MD5) Previous issue date: 2004-03-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Uma população de 118 RILs (linhagens recombinantes endogâmicas) foi obtida por meio do cruzamento entre o acesso BARC-8 (com alto teor de proteína) e a variedade brasileira Garimpo (com teor de proteína normal). Na geração F 9 foram abertas linhas, que constituíram o material genético utilizado neste trabalho. Noventa e cinco dessas RILs, cultivadas em dois ambientes distintos: Viçosa, MG e São Gotardo, MG, foram analisadas para as seguintes características: teor de proteína total em sementes de soja, teor das proteínas de reserva 11S e 7S e de suas respectivas subunidades, e da relação proteína total menos proteínas de reserva (PT-(11S+7S)). Quase todas estas características apresentaram uma distribuição aproximadamente normal (P<0,01), com exceção de proteína total em Viçosa. As herdabilidades das características avaliadas foram altas nos dois locais, entretanto, na análise conjunta, as herdabilidades foram menores devido ao efeito da interação genótipo X ambiente. Amostras do DNA das 118 RILs foram amplificadas com primers microssatélites, RAPD e AFLP. Análise de associação de marcas simples, regressão múltipla e mapeamento por intervalo composto foram utilizados para detectar e mapear as regiões genômicas associadas com estas características. Foram encontrados QTLs associados ao conteúdo de proteína total (GL I, que explica 14,74% da variação desta característica), ao conteúdo da subunidade α (GL G e GL C2, que explicam em conjunto 28,83% da variação desta característica), ao conteúdo da subunidade β (GL G e dois no grupo K, que explicam em conjunto 32,62% da variação desta característica), ao conteúdo de PT-(11S+7S) (GL D1b, que explica 13,71% da variação desta característica) e ao conteúdo de 7S (GL G e GL E) que explicam em conjunto 21,86% da variação desta característica no experimento de Viçosa. No experimento de São Gotardo, foram encontrados QTLs associados ao conteúdo de proteína total (GL 3 e I, que explicam em conjunto 11,42% da variação desta característica), ao conteúdo da subunidade α’ (GL A2, que explica 10,64% da variação desta característica), ao conteúdo das subunidades ácidas (GL 3, que explica 12,06% da variação desta característica), ao conteúdo de PT-(11S+7S) (GL I, que explica 11,34% da variação desta característica) e ao conteúdo de 11S (dois QTLS em diferentes fragmentos do GL K) que explicam em conjunto 20,88% da variação desta característica. Os marcadores associados ao teor de proteína foram diferentes de um local para outro, o que indica interação entre o genótipo e o ambiente. O grupo de ligação I foi associado a QTLs para proteína total em Viçosa e em São Gotardo. Este fato sugere que os locos associados presentes neste grupo de ligação contêm regiões com genes que são expressos em diferentes ambientes. / A 118 soybean RILs (recombinant inbreed lines) population was obtained by crossing the BARC-8 access (cultivar with high protein content) and the Brazilian variety Garimpo (with normal protein content). Lines from the F 9 generation constituted the genetic material used in this work. Ninety-five RILs cultivated in two different environments, Viçosa - MG and São Gotardo - MG, were analyzed following the characteristics: total protein content, storage protein content 11S and 7S and their respective subunits and relation of total protein minus storage proteins (PT-(11S+7S)). Almost all these characteristics presented a distribution approximately normal (P<0,001), except total protein in Viçosa. The heritability values of the characteristics were high in both places, however in a combined analysis; the heritability values were lower due to the effect of genotype x environment interaction. DNA samples of the 118 RILs were amplified with microsatellite primers, RAPD and AFLP. Analysis of association of simple markers, multiple regression and composed interval mapping were used to detect and map the genomic regions associated with these traits. QTLs (quantitative trait loci) associated with total protein content were found in GL I, that explains 14,7 % of the variation of this characteristic, with content of the a subunit in GL G and GL C2, that together explain 28,83% of the variation of this characteristic, with content of the ß subunit in GLG and two in group K, that together explain 32,62 % of the variation of this characteristic, with PT-(11S+7S) in GL D1b, that explains 13,71 % of the variation of this characteristic, and with content of 7S in GL G and GL E that together explain 21,86 % of the variation of this characteristic in the experiment conducted in Viçosa. QTLs associated with total protein content were found in the experiment conducted in São Gotardo in GL 3 and GL I, that together explain 11,42% of the variation of this characteristic, with content of the a’ subunit in GL A2, that explain 10,64 % of the variation of this characteristic, with content of acid subunits in GL 2, that explain 12,06 % of the variation of this characteristic, with PT-(11S+7S) in GL I, that explain 11,34 % of the variation of this characteristic and with the 11S content two QLTs in different GLK fragments that explain 20,88 % of the variation of this characteristic. The markers associated with protein content varied in different environment, indicating genotype and environment interaction. The linkage group I was associated with QTLs to total protein in Viçosa and São Gotardo. This suggests that total protein content loci associated with this linkage group contain regions with genes that express in different environments. / Tese importada do Alexandria, autor sem CPF
134

Molekulárně genetická variabilita v kandidátních QTL pro reprodukci u prasat

Putnová, Lenka January 2002 (has links)
No description available.
135

EVALUATION AND GENETIC ANALYSIS OF TWO SOYBEAN [Glycine max (L.) Merr.] RECOMBINANT INBRED LINE POPULATIONS SEGREGATING FOR RESISTANCE TO ROOT KNOT NEMATODE (Meloidogyne incognita)

Wright, Drew Welsey 01 December 2012 (has links)
One of the most economically important pathogens of US soybeans is the Southern Root Knot Nematode [(Meloidogyne incognita) (Kofoid and White) Chitwood] (Mi). Evaluation and identification of resistance is highly important to the plant breeding program at SIUC. The main objective of this study was to screen within the greenhouse two F5:7 recombinant inbred line (RIL) (n=96) from crosses between LS90-1920 or LS97-1610 (resistant parents) with `Spencer' (susceptible parent) to identify sources of resistance for Mi. Additionally, the RILs were evaluated in two locations in southern Illinois (Harrisburg and Dowell) in 2011 for several agronomic characteristics including yield performance. The phenotypic data collected from field and greenhouse experiments was used to select for superior lines within the two populations. The screening data was also used to identify single nucleotide polymorphism (SNP) markers associated with Mi resistance. Initial screening of the 5,361 SNP markers indicated four SNP markers (ss247062763, ss247064854, ss247077423 and ss247067293) highly associated with resistance to Mi. The results will help accelerating selection practices, and have provided high yielding resistant lines for the creation of resistant commercial varieties.
136

MENDELIZING QUANTITATIVE TRAIT LOCI THAT UNDERLIE RESISTANCE TO SOYBEAN SUDDEN DEATH SYNDROME

Lee, Yi-Chen 01 August 2016 (has links)
Soybean (Glycine max [L.] Merr.) cultivars differ in their resistance to sudden death syndrome (SDS). The syndrome is caused by root colonization by Fusarium virguliforme (ex. F. solani f. sp. glycines). Breeding for improve SDS response has proven challenging, possible due to interactions among the 18 known loci for resistance. Four loci for resistance to SDS (cqRfs to cqRfs3) were found clustered within 20 cM of the rhg1 locus underlying resistance to soybean cyst nematode (SCN) on chromosome 18. Another locus on chromosome 20 (cqRfs5) was reported to interact with this cluster. The aims of this study were to compare the inheritance of resistance to SDS in a near isogenic line (NIL) population that was fixed for resistance to SCN but still segregated at 2 of the 4 loci (cqRfs1 and cqRfs) for resistance to SDS on chromosome 18; to examine the interaction with the locus on chromosome 20; and to identify candidate regions underlying quantitative trait loci (QTL). Used were a near isogenic line population derived from residual heterozygosity in an F5:7 recombinant inbred line EF60 1-40; SDS response data from 2 locations and years; four microsatellite markers and six thousand SNP markers. Polymorphic regions were found from 2,788 to 8,938 Kbp on chromosome 18 and 33,100 to 34,943 Kbp on chromosome 20. Both regions were significantly (0.005 < P > 0.0001) associated with resistance to SDS. A fine map was constructed that Mendelized the three loci. Substitution maps suggested the two loci on chromosome 18 were actually 3 loci (cqRfs, cqRfs1 and cqRfs19). Candidate genes for cqRfs19 were identified in a small region of the genome sequence of soybean. An epistatic interaction was inferred where the allele of loci on chromosome 18 determined the value of the locus on chromosome 20. It was concluded that SDS loci are both complex and interacting which may explain the slow progress in breeding for resistance to SDS.
137

Identificação de QTLs candidatos associados à qualidade pós-colheita do pedúnculo de caju. / Detection of candidate QTLs associated the postharvest quality of cashew apple.

Santos, Francisco Herbeth Costa dos January 2008 (has links)
SANTOS, F. H. C. Identificação de QTLs candidatos associados à qualidade pós-colheita do pedúnculo de caju. 2008. 123 f. Dissertação (Mestrado em Agronomia/Fitotecnia) - Centro de Ciências Agrárias, Universidade Federal do Ceará, Fortaleza, 2008. / Submitted by Francisco Lacerda (lacerda@ufc.br) on 2014-07-03T19:51:39Z No. of bitstreams: 1 2008_dis_fhcsantos.pdf: 870825 bytes, checksum: b156596723b2a83893246b439a0299f3 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa(jairo@ufc.br) on 2014-07-16T20:10:54Z (GMT) No. of bitstreams: 1 2008_dis_fhcsantos.pdf: 870825 bytes, checksum: b156596723b2a83893246b439a0299f3 (MD5) / Made available in DSpace on 2014-07-16T20:10:54Z (GMT). No. of bitstreams: 1 2008_dis_fhcsantos.pdf: 870825 bytes, checksum: b156596723b2a83893246b439a0299f3 (MD5) Previous issue date: 2008 / Detection of quantitative trait loci (QTLs) and marker assisted selection associated with theses QTLs have shown a great interest in breeding programs focused on fruit quality traits. The aim of this work were to study the quality of cashew apple in several genotypes and identify QTLs associated with these traits, using the cashew genetic maps already developed. For the physical and physical-chemical analyses, it was collected 15 cashew apple per plant, from 66 genotypes of the generation F1 originated from the cross CCP 1001 x CP 96 and from the clone CCP 76, used as a control. The following characteristics were evaluated: color (lightness, redness and yellowness), weight (whole, nut and apple), apple length and diameter (upper and lower), oligomeric phenolic, total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ration and vitamin C. Detection of candidate QTLs were realized using the methods non-parametric mapping, interval mapping and multiple QTL mapping. The results evidence high phenotypic variability in the generation F1 for all characters analyzed, with potential for the selection of genotypes with the best characteristics for fresh fruit market. The QTL analyses showed 54 QTLs associated with quality of cashew apple. The characteristic redness presented the lowest number of QTL (two), while apple weight demonstrated the highest number (seven). These QTLs explained 3.15 to 21.33 % of the total phenotypic variance. The results strongly support the presence of true QTLs. These QTLs are in the process of validation to be used in the marker assisted selection in cashew breeding programs. / A identificação de locos que controlam características quantitativas (QTLs), e a seleção assistida por marcadores moleculares associados a esses QTLs, tem despertado grande interesse em programas de melhoramento visando à qualidade dos frutos. Objetivou-se com este estudo avaliar a qualidade de cajus em genótipos de cajueiro e identificar QTLs candidatos relacionados com estes caracteres, utilizando os mapas genéticos já desenvolvidos para o cajueiro. Para as análises físicas e físico-químicas foram coletados quinze cajus/planta em 66 plantas da geração F1 originada do cruzamento CCP 1001 x CP 96 e no clone CCP 76, utilizado como testemunha. Foram avaliadas as seguintes características: coloração (luminosidade, intensidade de vermelho e amarelo), pesos (total, castanha e pedúnculo), tamanho (comprimento, diâmetros basal e apical), fenólicos oligoméricos, sólidos solúveis totais, acidez total titulável, doçura e vitamina C. Para identificação dos QTLs candidatos foram utilizadas as metodologias de mapeamento não paramétrico, mapeamento de intervalo e mapeamento de QTLs múltiplos. Os resultados demonstraram elevada variação fenotípica na geração F1 para todos os caracteres em estudo, com potencial para seleção de genótipos que atendam as exigências do mercado in natura. As análises de QTLs permitiram a identificação de 54 QTLs associados a qualidade do pedúnculo. O caráter que apresentou o menor número de QTLs foi intensidade de vermelho, com dois, e o que apresentou o maior número foi o peso do pedúnculo, com sete. Estes QTLs explicaram entre 3,15 % e 21,33 % da variação fenotípica total. Os resultados obtidos suportam fortemente a presença de QTLs verdadeiros. Estes QTLs estão em processo de validação para que possam ser utilizados na seleção assistida por marcadores em programas de melhoramento genético do cajueiro.
138

Detekce polymorfismu DNA ve vztahu k mapování QTL u prasat

Knoll, Aleš January 1998 (has links)
No description available.
139

Mapeamento de QTLs para resistência a grãos ardidos causados por diplodia (Stenocarpella Sp.) em milho (Zea Mays L.)

Gutiérrez, Humberto Ignácio 28 February 2008 (has links)
Diplodia ear rot caused by the fungus Stenocarpella maydis (Berkeley) and Stenocarpella macrospora (Earle) have become one of the most important limiting factors for the production of Corn (Zea mays L.) in Brazil. The fungus can attack the stalks, leaves and the grain causing significant reductions on yield and the overall quality of the grain, since it can produce micotoxinas that are dangerous to livestock. Resistance to ear rot by Stenocarpella sp in corn is quantitative and highly influenced by the environment and even that artificial inoculation techniques are available to screen for the disease the overall cost is very expensive. The objective of this study was the identification of quantitative trait loci (QTL s) associated with ear rot resistance by Stenocarpella sp in one breeding population composed of 141 doublehaploid progenies resulted from the cross among the resistant inbred MONDR1 and the susceptible inbred MONDS1 in testcrosses with the susceptible tester MONDS5. Testcrosses were evaluated at harvest time after artificial inoculation for ear rot at three different locations in the central region of Brazil during the 2005/06 summer season. Thru Composite interval mapping (CIM), a total of three QTL s (LOD>2.5) for ear rot resistance were identified at chromosomes 2, 3 and 5, all together accounting for up 26% of total phenotypic variation for this character. The identification of two QTL s for ear rot resistance coming from the susceptible parent MONDS1 appear to indicate the presence of the phenomena of transgressive segregation. Additionally we were able to identify six double-haploid progenies with high level of resistance to ear rot by Stenocarpella (MDH15, MDH443, MDH95, MDH2, MDH120 e MDH81), being those recommended for their incorporation into the breeding program as new breeding sources for the Central Brazil regions. / Grãos ardidos causados pelos fungos Stenocarpella maydis (Berkeley) e Stenocarpella macrospora (Earle) tem se constituído num dos maiores fatores limitantes para a produção de milho (Zea mays L.) no Brasil. Estes fungos podem causar infecções no colmo, folhas e grãos, podendo ocasionar reduções significativas na produtividade e na qualidade do grão, pela produção de micotoxinas daninhas para aves e bovinos. A resistência para podridão de grão por Stenocarpella sp apresenta herança quantitativa e pode ser altamente influenciada pelo meio ambiente, e embora existam técnicas de inoculação que facilitam a discriminação de materiais suscetíveis, isto requer de grande quantidade de recursos. O objetivo do presente trabalho foi à identificação de locos de caracteres quantitativos (QTL) associados à resistência para podridão de grãos ( grãos ardidos ) ocasionados por Stenocarpella sp numa população de 141 progênies duplo-haplóides derivadas do cruzamento entre a linhagem resistente MONDR1 e a linhagem susceptível MONDS1 em testcross com o testador susceptível MONDS5. A porcentagem de espigas infectadas por Stenocarpella sp foi registrada para cada uma das testcrosses apos da inoculação artificial em três localidades na região Central de Brasil durante a Safra agrícola 2005/06. Mediante a análise de mapeamento por intervalo composto foram identificados três QTL s com LOD>2.5 para resistência à grãos ardidos nos cromossomos 2, 3 e 5, sendo estes em conjunto, responsáveis por ate 26% de variação fenotípica para este caráter. A identificação de dois QTL s para resistência a grãos ardidos por Stenocarpella sp com origem no progenitor susceptível parece indicar a presença do fenômeno de segregação transgressiva. Adicionalmente foram identificadas seis progênies duplohaplóides com alto nível de resistência a grãos ardidos (MDH15, MDH443, MDH95, MDH2, MDH120 e MDH81), sendo estas recomendadas para sua incorporação no programa de melhoramento para a região central do Brasil. / Mestre em Genética e Bioquímica
140

Associação de marcadores (AFLP) com caracteres de interesse agronômico em clones elite de cana-de-açúcar (Sccharum spp)

Diniz, Michely Correia January 2007 (has links)
Made available in DSpace on 2014-06-12T18:05:08Z (GMT). No. of bitstreams: 2 arquivo6214_1.pdf: 2321884 bytes, checksum: a888b18416f7d4f41fb143eb0c9019a9 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / O Brasil é o maior produtor de cana-de-açúcar que é uma das principais biomassas. O etanol, obtido da fermentação do caldo de cana-de-açúcar, é um combustível potencialmente global, por amenizar dois problemas mundiais, a escassez do petróleo e o efeito estufa. O melhoramento da cana-de-açúcar requer muitas avaliações (diferentes anos e locais), assim sendo o uso de marcadores moleculares pode auxiliar esse processo. A técnica de AFLP (Amplified Fragment Length Polymorphisms), de caráter multiplex, é ótima para geração de um grande número de marcadores a partir de poucas combinações de iniciadores. Este trabalho teve por objetivo detectar associações fenótipo-marcador em progênie (234/96) de híbridos de clones elites do melhoramento nacional de cana-deaçúcar, a partir de marcadores AFLP e os caracteres Fibra%Cana, PCC (POL%Cana) e TCH (tonelagem de cana por hectare), oriundos de oito ensaios, que avaliaram os dois ciclos da cultura (cana-planta e cana-soca) em duas localidades (Piracicaba e Jaú, ambas em SP). Foram detectados marcadores associados a prováveis QTLs (locos controladores de caracteres quantitativos), tanto de efeitos positivos quanto negativos, e para os três caracteres, individualmente. Alguns marcadores apresentaram também associação conjunta significativa (p < 0.05) para mais de um caráter. A seqüência de DNA de um marcador AFLP possibilitou o desenho de iniciadores específicos que amplificaram via PCR, com DNAs da progênie 234/96, três marcadores de efeitos negativos associados com Fibra%Cana, sendo um deles também associado com TCH e de efeito positivo. Esses marcadores foram considerados promissores para uso em Seleção Assistida, auxiliando os programas de melhoramento

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