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Preparation of a partial gene library, detection of DNA polymorphisms and chromosome studies in the fern PteridiumJubrael, J. M. S. January 1987 (has links)
No description available.
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Genetic epidemiology of breast cancer in Cyprus : a case-control study of DNA repair genesLiozidou, Maria January 2009 (has links)
The occurrence of early-onset breast cancer (EOBC) has been associated with germline mutations in the BRCA1 and BRCA2 genes. The first aim of this thesis was to evaluate the frequency and distribution of mutations in these genes, in a group of Cypriot women diagnosed with EOBC. Pathogenic mutations were identified in 6 of the 26 unrelated patients. This study supports a strong correlation between the early onset breast cancer phenotype and the presence of pathogenic BRCA1/2 mutations. It is of interest that pathogenic mutations were detected in patients without a family history of the disease. Based on these results, we recommend that BRCA1/2 screening should be offered to patients with a diagnosis of EOBC irrespective of their family history. The known breast cancer susceptibility genes explain only about 5% of breast cancer cases. Thus, it is likely that other breast cancer susceptibility genes exist. The second aim of the present thesis was to assess whether alterations in DNA repair genes modify breast cancer risk in the Cypriot population. Towards this objective, blood samples were collected and genomic DNA isolated from 1109 Cypriot female breast cancer patients diagnosed between 40-70 years old, and from 1177 age-matched healthy female controls. A total of 79 single nucleotide polymorphisms (SNPs) were genotyped in all samples. Significant associations with breast cancer risk were observed for eight of the SNPs studied. Five SNPs in the BRCA2, MRE11A, MUS81, PBOV1 and XRCC1 genes, were associated with an increased risk for breast cancer, while two SNPs in the NBS1 gene and one SNP in the MRE11A gene appeared to be associated with reduced risk for the disease. The data from this study support the hypothesis that genetic variants in DNA repair genes influence breast cancer risk and provides further evidence for the existence of a polygenic model for breast cancer.
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Identification of single nucleotide polymorphisms within the OCT2 gene in the South African black populationWilson, Nina Claire January 2016 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / The Organic Cation Transporter 2 (OCT2) gene is responsible for facilitating the transport of
cationic compounds, which include both endogenous substrates and clinical drugs. Single
nucleotide polymorphisms (SNPs) within this gene were extensively explored in the South
African black population as little research has been conducted on these individuals so far. We
sequenced the OCT2 promoter region of 10 DNA samples from the South African black
population and identified four SNPs and one INDEL. We performed a luciferase assay to
determine their effects on gene expression and we found two variants (rs59695691 and
rs138765638) that showed a statistically significant change in luciferase expression
suggesting that they may be associated with a change in OCT2 regulatory function. We also
indentified thirteen SNPs and two INDELs within the OCT2 promoter region, and nine SNPs
within the OCT2 coding region through analysing various South African population studies.
These variations could affect both gene expression and protein function. These findings help
contribute to filling the gap pertaining to OCT variation in South African populations. / LG2017
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Computational identification of synonymous SNPs in the human genome and their potential role in diseaseWood, Lee-Ann 25 January 2013 (has links)
The potential phenotypic effects of synonymous SNPs (sSNPs) have long been overlooked. Although
several sSNPs are no longer thought to be silent, no one has identified which sSNPs may contribute
to phenotypic variation on a genome-wide scale. sSNPs that cause a change in codon-usage
frequency or mRNA secondary structures may alter translational and protein folding kinetics. In
addition, sSNPs that alter splice-site consensus sequences may cause aberrant slicing, which could
change the protein product. A sSNP that contributes to any of these molecular mechanisms may
thus alter protein structure and function. To computationally identify sSNPs with a potential impact,
SynSNP was created. SynSNP is a text-based tool written in Python. All sSNPs published within
dbSNP are first identified. SynSNP uses established bioinformatics tools to determine which of the
sSNPs may potentially result in a molecular effect. The potentially functional sSNPs are then
assessed to determine whether any have previously been associated with a trait or disease in
genome-wide association studies (GWAS) and/or occur within genes known to be associated with
disease in OMIM (Online Mendelian Inheritance in Man). Of the 90,102 identified sSNPs, 21,086
(23.4%) were predicted to potentially have a functional impact, through one or more of the three
molecular mechanisms investigated. Of the sSNPs predicted to potentially have a functional impact,
14 (0.07%) had previously been associated with a trait or disease in GWAS. A subset of 4,057
(19.2%) of the potentially functional sSNPs were within genes known to be associated with disease
in OMIM. Only six (0.03%) of the potentially functional sSNPs had previously been associated with a
trait or disease in GWAS and occurred within genes known to be associated with disease in OMIM.
SynSNP could be developed further to aid the discovery of more sSNPs with a potential functional
impact. A significant proportion of sSNPs may have a functional impact and their potential role in
disease should therefore not be underestimated or neglected.
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A physiologically based pharmacokinetic model to characterise the association between CYP2B6 polymorphisms and efavirenz pharmacokinetics in pregnancyJulsing, Andrea Alison January 2017 (has links)
A research report submitted to the faculty of health science, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of MSC MED pharmaceutical affairs / MT2017
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The Influence of the CYP2C19 and CYP2D6 genetic polymorphisms on oxidative drug metabolismColler, Janet K. January 1999 (has links) (PDF)
Amendements: leaves 252-254. Copies of author's previously published articles inserted. Bibliography: leaves 226-251. The CYP2C19 and CYP2D6 genetic polymorphisms control the oxidative metabolism of many different drug classes. Populations are separated into groups of extensive metabolisers (EM), poor metabolisers (PM), and in the case of CYP2D6, ultra-rapid metabolisers (UM). In vitro studies using human liver microsomes were conducted to examine the kinetics of the oxidative metabolism of flunitrazepam, and which CYP450 enzymes mediate the oxidative metabolism of flunitrazepam, (S)-mephenytoin and proguanil.
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Ecological genetics of two polymorphic enzymes in three species of Megalorchestia (Amphipoda:Talitridae)McDonald, John H. 16 December 1983 (has links)
Graduation date: 1984
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Single nucleotide polymorphism diversity in domesticated and wild sunflowersFreeman, Carrie 16 September 2003 (has links)
Single nucleotide polymorphisms (SNPs) are the most common DNA
polymorphisms in plant and animal genomes. SNPs were identified in the allele
sequences of up to 12 sunflower (Helianthus annuus L.) genotypes for a genome-wide
sample of 81 loci originally mapped using restriction fragment length
polymorphism (RFLP) markers. The RFLP loci anchor a dense RFLP linkage
map and second-generation linkage maps constructed using simple sequence
repeats and other high-throughput DNA markers. The goal of this study was to
develop high-throughput SNP markers for the cDNA-RFLP loci for linkage
mapping, diversity analysis, and molecular breeding and genomics research. The
specific objectives were to: (i) develop FP-TDI or fluorescent primer-extension
SNP assays for the cDNA-RFLP loci; (ii) validate the SNP markers by screening
12 sequenced (reference) genotypes; and (iii) assess the utility and polymorphism
rate of the SNP markers across a genetically diverse panel of unsequenced wild
and domesticated sunflower genotypes.
SNP markers were successfully developed for 44 of the targeted 49 cDNA-RFLP
loci. Thirty-one of the SNP markers were further selected for a diversity
analysis across a genetically diverse panel of wild and domesticated sunflower
genotypes. The mean heterozygosity (H) score for the loci was 0.41, which nears
the maximum H score of 0.5 for biallelic markers. SNPs in this study exhibited
polymorphism rates close to those of RFLP and SSR markers in inbred sunflower
lines. / Graduation date: 2004
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Mechanistic studies on the polymorphism at -77GT repeats regions of IFNAR1 and its correlation to the susceptibility to chronic HBV infectionZeng, Yong, January 2009 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 77-109). Also available in print.
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Genetic polymorphisms in ovarian cancer黎子韻, Lai, Tsz-wan, Kristi. January 2002 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
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