• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 3
  • 2
  • Tagged with
  • 9
  • 9
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 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.
1

Analysis of high-density SNP data from complex populations

Floyd, James A. B. January 2011 (has links)
Data from a Croatian isolate population are analysed in a genome-wide association study (GWAS) for a variety of disease-related quantitative traits. A novel genomewide approach to analysing pedigree-based association data called GRAMMAR is utilised. One of the significant findings, for uric acid, is followed up in greater detail, and is replicated in another isolate population, from Orkney. The associated SNPs are located in the SLC2A9 gene, coding for a known glucose transporter, which leads to identification of SLC2A9 as a urate transporter too (Vitart et al., 2008). These SNPs are later implicated in affecting gout, a disease known to be linked with high serum uric acid levels, in an independent study (Dehghan et al., 2008). Subsequently, investigation into different ways in which to use SNP data to identify quantitative trait loci (QTL) for genome-wide association (GWA) studies is performed. Several multi-marker approaches are compared to single SNP analysis using simulated phenotypes and real genotype data, and results show that for rare variants haplotype analysis is the most effective method of detection. Finally, the multi-marker methods are compared with single SNP analysis on the real uric acid data. Interpretation of real data results was complicated due to low sample size, since only founder and unrelated individuals may be used for population-based haplotype analysis, nonetheless, results of the prior analyses of simulated data indicate that multi-marker methods, in particular haplotypes, may greatly facilitate detection of QTL with low minor allele frequency in GWA studies.
2

Mucopolissacaridose IVA : análise molecular e caracterização de haplótipos intragênicos no gene Galns

Bochernitsan, Aline Nemetz January 2015 (has links)
Introdução: Mucopolissacaridose IVA é uma doença lisossômica, autossômica recessiva, causada pela deficiência da enzima N-acetilgalactosamina-6-sulfatase. É uma doença rara e a incidência varia de 1:76.000 a 1:640.000 recém-nascidos vivos. Até o momento 319 diferentes mutações causadoras da doença já foram identificadas, o que demonstra a ampla variabilidade genética. Objetivo: Caracterizar o genótipo de pacientes com MPS IVA, analisar 6 polimorfismos intragênicos e identificar os haplótipos presentes em nossos pacientes, através do estudo molecular do gene GALNS. Métodos: O estudo foi realizado em 45 pacientes provenientes das regiões Nordeste, Sudeste, e Sul do Brasil, com diagnóstico bioquímico confirmado para MPS IVA. A análise molecular foi realizada através de PCR seguida de sequenciamento, pelo método de Sanger, a fim de identificar as mutações causadoras da doença. Para o estudo de haplótipos foram analisados 6 polimorfismos intragênicos através de PCR em Tempo Real, pelo método Taqman, em pacientes e controles. Resultados: A análise do gene GALNS, nos 45 pacientes, permitiu a identificação de 18 diferentes mutações, e a caracterização de 6 haplótipos distintos. Das 18 mutações encontradas, 5 apresentaram uma alta frequência (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser), além disso, foram encontradas 4 novas mutações em outros três pacientes (p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G). Dentre as mutações encontradas com maior frequência, a mutação p.Ser341Arg foi identificada em um maior número de pacientes, sendo a maioria proveniente da região Nordeste. Além disso, todos os pacientes com esta mutação apresentaram um único haplótipo. Conclusão: Os resultados obtidos permitiram a identificação de 18 mutações dentre elas 4 novas mutações. A alta frequência da mutação p.Ser341Arg no Nordeste do Brasil, principalmente no estado da Paraíba nos leva a inferir um possível efeito fundador da doença. Esta mutação foi observada somente na população brasileira e todos os pacientes com mutação em homozigose apresentaramum único haplótipo. Estas análises são importantes para identificar portadores nas famílias, para diagnóstico pré-natal, e também como forma de identificar uma origem comum em mutações frequentes em determinadas populações. / Background: Mucopolysaccharidosis IVA is an autosomal recessive lysosomal disease, caused by deficiency of N-acetilgalactosamina-6-sulfatase. It is a rare disease and the incidence ranges from 1: 76,000 to 1:640,000 live births. To date 319 mutations have been identified in this gene, demonstrating the wide variability of disease causing mutations. Objective: Analyze and characterize the genotype of patients with MPS IVA, through molecular analysis of GALNS. Methods: Molecular analysis of 45 patients with confirmed biochemical diagnosis for MPS IVA was performed. Mutation analysis was performed by PCR followed by Sanger sequencing. Haplotype analysis was performed using 6 intragenic polymorphisms by Real-Time PCR. Results: In this study we found 18 different mutations among 45 Brazilian patients and identified 5 common mutations (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser). Four novel mutations were also identified through molecular analysis, including: p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G. Patients are distributed in Northeast, Southeast and South regions of Brazil. Six different haplotypes were identified among patients. The p.Ser341Arg mutation showed the highest frequency, and most patients are located in the Northeast, additionally, all patients with this mutation show the same haplotype.Conclusion: These analyzes are important to identify carriers in families, for prenatal diagnosis, and in order to identify the mutation origin when certain recurrent mutation is associated with the same haplotype. In this study, we observed a high frequency of p.Ser341Arg mutation in Northeast, mainly in the state of Paraíba. This mutation was detected with higher frequency among patients, and showed only a haplotype. This mutation is unique for the Brazilian population and thus, we could suggest that a possible founder effect for this mutation could exist.
3

Mucopolissacaridose IVA : análise molecular e caracterização de haplótipos intragênicos no gene Galns

Bochernitsan, Aline Nemetz January 2015 (has links)
Introdução: Mucopolissacaridose IVA é uma doença lisossômica, autossômica recessiva, causada pela deficiência da enzima N-acetilgalactosamina-6-sulfatase. É uma doença rara e a incidência varia de 1:76.000 a 1:640.000 recém-nascidos vivos. Até o momento 319 diferentes mutações causadoras da doença já foram identificadas, o que demonstra a ampla variabilidade genética. Objetivo: Caracterizar o genótipo de pacientes com MPS IVA, analisar 6 polimorfismos intragênicos e identificar os haplótipos presentes em nossos pacientes, através do estudo molecular do gene GALNS. Métodos: O estudo foi realizado em 45 pacientes provenientes das regiões Nordeste, Sudeste, e Sul do Brasil, com diagnóstico bioquímico confirmado para MPS IVA. A análise molecular foi realizada através de PCR seguida de sequenciamento, pelo método de Sanger, a fim de identificar as mutações causadoras da doença. Para o estudo de haplótipos foram analisados 6 polimorfismos intragênicos através de PCR em Tempo Real, pelo método Taqman, em pacientes e controles. Resultados: A análise do gene GALNS, nos 45 pacientes, permitiu a identificação de 18 diferentes mutações, e a caracterização de 6 haplótipos distintos. Das 18 mutações encontradas, 5 apresentaram uma alta frequência (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser), além disso, foram encontradas 4 novas mutações em outros três pacientes (p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G). Dentre as mutações encontradas com maior frequência, a mutação p.Ser341Arg foi identificada em um maior número de pacientes, sendo a maioria proveniente da região Nordeste. Além disso, todos os pacientes com esta mutação apresentaram um único haplótipo. Conclusão: Os resultados obtidos permitiram a identificação de 18 mutações dentre elas 4 novas mutações. A alta frequência da mutação p.Ser341Arg no Nordeste do Brasil, principalmente no estado da Paraíba nos leva a inferir um possível efeito fundador da doença. Esta mutação foi observada somente na população brasileira e todos os pacientes com mutação em homozigose apresentaramum único haplótipo. Estas análises são importantes para identificar portadores nas famílias, para diagnóstico pré-natal, e também como forma de identificar uma origem comum em mutações frequentes em determinadas populações. / Background: Mucopolysaccharidosis IVA is an autosomal recessive lysosomal disease, caused by deficiency of N-acetilgalactosamina-6-sulfatase. It is a rare disease and the incidence ranges from 1: 76,000 to 1:640,000 live births. To date 319 mutations have been identified in this gene, demonstrating the wide variability of disease causing mutations. Objective: Analyze and characterize the genotype of patients with MPS IVA, through molecular analysis of GALNS. Methods: Molecular analysis of 45 patients with confirmed biochemical diagnosis for MPS IVA was performed. Mutation analysis was performed by PCR followed by Sanger sequencing. Haplotype analysis was performed using 6 intragenic polymorphisms by Real-Time PCR. Results: In this study we found 18 different mutations among 45 Brazilian patients and identified 5 common mutations (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser). Four novel mutations were also identified through molecular analysis, including: p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G. Patients are distributed in Northeast, Southeast and South regions of Brazil. Six different haplotypes were identified among patients. The p.Ser341Arg mutation showed the highest frequency, and most patients are located in the Northeast, additionally, all patients with this mutation show the same haplotype.Conclusion: These analyzes are important to identify carriers in families, for prenatal diagnosis, and in order to identify the mutation origin when certain recurrent mutation is associated with the same haplotype. In this study, we observed a high frequency of p.Ser341Arg mutation in Northeast, mainly in the state of Paraíba. This mutation was detected with higher frequency among patients, and showed only a haplotype. This mutation is unique for the Brazilian population and thus, we could suggest that a possible founder effect for this mutation could exist.
4

Mucopolissacaridose IVA : análise molecular e caracterização de haplótipos intragênicos no gene Galns

Bochernitsan, Aline Nemetz January 2015 (has links)
Introdução: Mucopolissacaridose IVA é uma doença lisossômica, autossômica recessiva, causada pela deficiência da enzima N-acetilgalactosamina-6-sulfatase. É uma doença rara e a incidência varia de 1:76.000 a 1:640.000 recém-nascidos vivos. Até o momento 319 diferentes mutações causadoras da doença já foram identificadas, o que demonstra a ampla variabilidade genética. Objetivo: Caracterizar o genótipo de pacientes com MPS IVA, analisar 6 polimorfismos intragênicos e identificar os haplótipos presentes em nossos pacientes, através do estudo molecular do gene GALNS. Métodos: O estudo foi realizado em 45 pacientes provenientes das regiões Nordeste, Sudeste, e Sul do Brasil, com diagnóstico bioquímico confirmado para MPS IVA. A análise molecular foi realizada através de PCR seguida de sequenciamento, pelo método de Sanger, a fim de identificar as mutações causadoras da doença. Para o estudo de haplótipos foram analisados 6 polimorfismos intragênicos através de PCR em Tempo Real, pelo método Taqman, em pacientes e controles. Resultados: A análise do gene GALNS, nos 45 pacientes, permitiu a identificação de 18 diferentes mutações, e a caracterização de 6 haplótipos distintos. Das 18 mutações encontradas, 5 apresentaram uma alta frequência (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser), além disso, foram encontradas 4 novas mutações em outros três pacientes (p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G). Dentre as mutações encontradas com maior frequência, a mutação p.Ser341Arg foi identificada em um maior número de pacientes, sendo a maioria proveniente da região Nordeste. Além disso, todos os pacientes com esta mutação apresentaram um único haplótipo. Conclusão: Os resultados obtidos permitiram a identificação de 18 mutações dentre elas 4 novas mutações. A alta frequência da mutação p.Ser341Arg no Nordeste do Brasil, principalmente no estado da Paraíba nos leva a inferir um possível efeito fundador da doença. Esta mutação foi observada somente na população brasileira e todos os pacientes com mutação em homozigose apresentaramum único haplótipo. Estas análises são importantes para identificar portadores nas famílias, para diagnóstico pré-natal, e também como forma de identificar uma origem comum em mutações frequentes em determinadas populações. / Background: Mucopolysaccharidosis IVA is an autosomal recessive lysosomal disease, caused by deficiency of N-acetilgalactosamina-6-sulfatase. It is a rare disease and the incidence ranges from 1: 76,000 to 1:640,000 live births. To date 319 mutations have been identified in this gene, demonstrating the wide variability of disease causing mutations. Objective: Analyze and characterize the genotype of patients with MPS IVA, through molecular analysis of GALNS. Methods: Molecular analysis of 45 patients with confirmed biochemical diagnosis for MPS IVA was performed. Mutation analysis was performed by PCR followed by Sanger sequencing. Haplotype analysis was performed using 6 intragenic polymorphisms by Real-Time PCR. Results: In this study we found 18 different mutations among 45 Brazilian patients and identified 5 common mutations (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser). Four novel mutations were also identified through molecular analysis, including: p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G. Patients are distributed in Northeast, Southeast and South regions of Brazil. Six different haplotypes were identified among patients. The p.Ser341Arg mutation showed the highest frequency, and most patients are located in the Northeast, additionally, all patients with this mutation show the same haplotype.Conclusion: These analyzes are important to identify carriers in families, for prenatal diagnosis, and in order to identify the mutation origin when certain recurrent mutation is associated with the same haplotype. In this study, we observed a high frequency of p.Ser341Arg mutation in Northeast, mainly in the state of Paraíba. This mutation was detected with higher frequency among patients, and showed only a haplotype. This mutation is unique for the Brazilian population and thus, we could suggest that a possible founder effect for this mutation could exist.
5

Genetics of complement proteins among Swedish newborns

Sun, Xinyao January 2022 (has links)
Complement proteins play an important role in the body's immune processes and involve in the pathology of many diseases in human, such as major depressive disorder and schizophrenia. Understanding the genetics of those proteins is an important step toward unraveling their effects on psychiatric disorders.  The complement protein levels differ between neonates and adults. There are many studies investigating the genetic architecture of the complement proteins, but evidence about the genetics of neonatal complement proteins is scarce. In this study, I investigated the SNPs and haplotypes that are associated with the five complement proteins, C1q, C3, C4, CFB, and CFH among newborns. I also compared the effects of the identified SNPs among neonates and adults. This study uses 75 samples from Swedish newborns whose blood were primarily collected for Phenylketonuria screening. Genotype data and protein levels were measured from dried blood spots. To investigate the genetics of the complement proteins, I first conducted single SNPs association analyses. The single SNPs used in this study was derived from previous research of European adult samples and has been shown to be significantly associated with the target protein. Then, after imputing the SNPs for the MHC region, I conducted haplotype analysis in the MHC region for the five complement proteins. Finally, I compared the effects of the variants identified in the single SNPs association analysis with the effects that were reported for adult protein levels in previous studies. The results of single SNP association analysis showed that among the 14 SNPs that were associated with adult protein levels, SNP rs4151669 that associated with complement factor B (CFB) was significantly associated with the target protein in the neonatal population. Some SNPs (rs8283, rs4151669 and rs10737680) may have opposite effects in the two populations. This study found 86 haplotypes potentially associated with the complement proteins. Among them, the haplotype “H840” which located at chr6:32594217-32597172 was significantly associated with five complement proteins. This study provides evidence for the genetic component of the 5 complement protein levels among neonates. The results also suggested that the genetic influence of the complement protein among adult and neonatal population are different.
6

Preimplantační genetická haplotypizace v geneticky rizikových rodinách / Preimplantation genetic haplotyping in genetically risk families

Borgulová, Irena January 2018 (has links)
PREIMPLANTATION GENETIC HAPLOTYPING IN GENETICALLY RISK FAMILIES Abstract of Irena Borgulova's PhD study Page 1/1 ABSTRACT Preimplantation genetic diagnosis (PGD) is at the intersection of assisted reproduction and clinical genetics. PGD precedes prenatal diagnosis because consists in biopsy of a single embryonic cell and its examination excluding genetic risks before embryo transfer back to mother uterus. Methods within PGD can offer all spectrums of possible investigations of a single cell, whether focused on monogenic disorders, chromosomal aberration or abnormality of whole genome. Monogenic diseases in embryos can be detected by direct or indirect linkage analysis. Indirect linkage analysis has the advantage compared to direct analysis that it is able to indentify pertinent aberration of examined chromosome. Indirect linkage analysis is characterised by preimplantation genetic haplotyping (PGH) which is prime and important constituent of PGD cycle. PGH is based on family anamnesis for determination of pathologic/ high-risk (mutation-associated) haplotype and healthy/ low-risk (without mutation) haplotype by comparison with the haplotypes of other family members. PGD cycle requires in vitro fertilisation (IVF). IVF cycle includes hormonal stimulation, biopsy of oocytes and their fertilisation outside...
7

Long QT syndrome in Sweden : founder effects and associated cardiac phenotypes / Långt QT syndrom i Sverige : foundereffekter och associerade kardiella fenotyper

Winbo, Annika January 2012 (has links)
Background: We aimed to increase the knowledge regarding the familial arrhythmogenic disorder Long QT Syndrome (LQTS) and its recessive variant Jervell and Lange-Nielsen Syndrome (JLNS) in Sweden, including prevalences and clinical phenotypes. A specific focus was directed towards two KCNQ1 mutations –p.Y111C and p.R518X- commonly identified in Swedish LQTS index cases. Methods: Cases and families with LQTS (p.Y111C or p.R518X) and JLNS were recruited via regional clinical practices, national referrals to the Clinical Genetics laboratory, Umeå University Hospital, and a national inventory. Molecular genetics methods were used for case ascertainment. Clinical data was obtained via medical records, a questionnaire, and/or an interview. Electrocardiograms were manually assessed. In p.R518X heterozygotes intra-familial phenotypic variability (QTc and cardiac events) was assessed by analysis of sequence variants (modifier genes). The origins of the mutations p.Y111C and p.R518X were investigated using genealogical and haplotype analysis (microsatellite markers). In families sharing a common haplotype mutation age and associated prevalence was analyzed using ESTIAGE and DMLE computer software. Results: We identified p.Y111C (170 mutation-carriers) and p.R518X (101 mutation-carriers) as two major causes of LQTS/JLNS in Sweden. LQTS phenotype was revealed to be relatively benign in p.Y111C and p.R518X (annual incidence of life-threatening cardiac events, before therapy 0.05% and 0.04%, respectively). Gender-specific effects of genetic modifiers on phenotypic expression were seen. A founder origin, approximately 600-700 years ago in two northern river valleys was established for p.Y111C and p.R518X, and a high prevalence of LQTS founder descendants suggested. A minimum JLNS prevalence of 1:200 000 in preadolescent Swedish children was revealed. JLNS phenotype was mainly severe, with a cumulative incidence of life-threatening cardiac events of 53% (annual incidence rate before therapy 5%) and four sudden deaths. Possible founder effects regarding four KCNQ1 mutations; p.Y111C (8%), p.R518X (50%), c.572_576del (17%) and p.Q530X (8%) together explained 83% of the JLNS mutation-spectrum in Sweden, consisting of 8 KCNQ1 mutations. Conclusion: The high prevalence of p.Y111C- and p.R518X-related LQTS as well as JLNS revealed in Sweden could be explained by the combination of mild clinical phenotypes in heterozygotes and strong founder effects present during the population development of northern Sweden. Increased knowledge regarding the occurrence of LQTS and JLNS as well as mutation- and/or genotype-specific data constitute prerequisites for possible improvement of patient management.
8

Molekulárně genetická analýza pacientů s Usherovým syndromem / Molecular genetic analysis of patients with Usher syndrome

Průšová, Kateřina January 2020 (has links)
The work focuses on molecular genetic testing of patients with Usher syndrome to confirm the diagnosis, to determine the causal cause of the disease and describe new mutations causing Usher syndrome in Czech patients. Usher syndrome is a clinically and genetically heterogeneous disease that is the most common cause of hereditary deafblindness. Based on responsible genes and disease onset is classified into three clinical subtypes. Given the fact that there is currently no specific treatment, there is a need to understand the pathophysiology of this disease and to broaden the spectrum of causal mutations. The theoretical part of the thesis deals with the anatomy of the eye, especially the structure of the retina. Attention is also paid to retinal diseases, such as the progressive loss of vision characteristic for retinitis pigmentosa (RP). RP may occur either as an isolated disorder or also affecting other organs, so-called syndromic RP. Classic syndromic RP includes Usher's syndrome, which the work mainly deals with. The theoretical part of the thesis describes mainly the mechanism of the disease, the functions of individual Usher proteins and the genes that encode these proteins. The haplotype analysis has been previously done for the most common mutations causing Usher's syndrome in Europe Based...
9

Analysis of genetic polymorphisms for statistical genomics: tools and applications

Morcillo Suárez, Carlos 19 December 2011 (has links)
New approaches are needed to manage and analyze the enormous quantity of biological data generated by modern technologies. Existing solutions are often fragmented and uncoordinated and, thus, they require considerable bioinformatics skills from users. Three applications have been developed illustrating different strategies to help users without extensive IT knowledge to take maximum profit from their data. SNPator is an easy-to-use suite that integrates all the usual tools for genetic association studies: from initial quality control procedures to final statistical analysis. CHAVA is an interactive visual application for CNV calling from aCGH data. It presents data in a visual way that helps assessing the quality of the calling and assists in the process of optimization. Haplotype Association Pattern Analysis visually presents data from exhaustive genomic haplotype associations, so that users can recognize patterns of possible associations that cannot be detected by single-SNP tests. / Calen noves aproximacions per la gestió i anàlisi de les enormes quantitats de dades biològiques generades per les tecnologies modernes. Les solucions existents, sovint fragmentaries i descoordinades, requereixen elevats nivells de formació bioinformàtica. Hem desenvolupat tres aplicacions que il•lustren diferents estratègies per ajudar als usuaris no experts en informàtica a aprofitar al màxim les seves dades. SNPator és un paquet de fàcil us que integra les eines usades habitualment en estudis de associació genètica: des del control de qualitat fins les anàlisi estadístiques. CHAVA és una aplicació visual interactiva per a la determinació de CNVs a partir de dades aCGH. Presenta les dades visualment per ajudar a valorar la qualitat de les CNV predites i ajudar a optimitzar-la. Haplotype Pattern Analysis presenta dades d’anàlisi d’associació haplotípica de forma visual per tal que els usuaris puguin reconèixer patrons de associacions que no es possible detectar amb tests de SNPs individuals.

Page generated in 0.0742 seconds