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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.
361

Genome-Wide Association Study on the Sleep Symptom of Post Traumatic Stress Disorder

Pooler, Tammy 01 January 2015 (has links)
Posttraumatic stress disorder (PTSD) is a psychiatric condition that presents with 3 main symptoms're-experiencing, avoidance/numbing, and hyper arousal'after an individual experiences a traumatic event. Recent evidence suggests a potential genetic basis for PTSD and a sub symptom of hyper arousal, sleep, as a potential pathway for PTSD development, but no study has identified candidate genes associated with specific symptoms such as sleep difficulty. Based on a conceptual framework in which specific genes are associated with the onset of PTSD, this study used a genome-wide association study (GWAS) method with a case control study design to compare the genomes of individuals with and without PTSD. A secondary GWAS dataset from a study on alcohol dependence in European and African Americans was obtained from the National Center for Biotechnology Information. PTSD cases and controls were analyzed using PLINK software. Signals from 2 single nucleotide polymorphisms (SNPs), which have not been previously associated with PTSD, exceeded the established genome-wide threshold: SNP rs13160949 on chromosome 5 (p = 7.33x10-9, OR: 1.565) and SNP rs2283877 on chromosome 22 (p = 2.55x10-8, OR: 1.748). Neither SNP, though, maintained genomewide significance following corrected tests for multiple testing, population stratification, and false discovery, so the planned analysis for possible associations with PTSD by symptom category then by the sub symptom of sleep could not be completed. The results of this study suggest that PTSD may be the result of polygenic SNPs with weak effects, which supports a recent study indicating the disease may be highly polygenic. Positive social change implications include bringing attention to the clinical and research community that PTSD may involve complex polygenic factors in need of further study.
362

Analysis of Single Nucleotide Polymorphism Panels for Bovine DNA Identification

Blanchard, Kimberly A. 01 May 2013 (has links)
Single nucleotide polymorphisms (SNPs) are single base-pair variations that exist between individuals. There are approximately a million or more SNPs located throughout the genome of each individual animal. Therefore, by taking advantage of these unique polymorphisms, SNPs can be used to resolve questions of unknown parentage in the livestock industry. Currently a panel of 88 SNPs, obtained from a panel of 121 SNPs originally created by USDA-MARC, is commercially available from Fluidigm®. The objective of this study was to determine whether the number of SNPs from the 88-SNP marker panel could be reduced to form a smaller, more cost-efficient parentage-testing SNP panel. A smaller panel would benefit farmers and researchers alike in reducing the time spent in running and analyzing the test, as well as reducing the overall cost for the procedure. Genotype data from over 3000 cattle samples containing offspring and potential parents were examined using two parentage calling software packages. Parentage assessment was analyzed using nine SNP panels of varying size. It was determined that a panel of 71 SNPs, chosen from the original 88 SNPs, was the minimum number required to maintain statistical accuracy and reliability.
363

Understanding the Relationship Between HERC2 and OCA2 Variants and Iris Pigmentation Genetics

Wallpe, Clarissa 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Externally visible characteristics (EVCs) predicted from an unknown sample of DNA are particularly useful in forensics as they can provide information beyond that of an STR profile. Current EVCs which are highly studied and well-predicted include iris, hair, and skin color. Notably, models predicting iris color, such as IrisPlex, are the most accurate with up to ~95% accuracy; however, some inaccurate predictions occur, as is evidenced by the ~5%. Often, these are due to green or hazel eyes, which are frequently viewed as intermediate. Though, some of the inaccurate predictions are due to true-blue being predicted as brown and vice versa. Previous research has theorized the possibility of two SNPs, rs12913832 and rs1800407, acting as a functional haplotype affecting iris color. rs12913832 is recognized as the most predictive SNP for iris color and highly significant in other pigmentation phenotypes; presently, rs1800407 is the second-ranked SNP in the IrisPlex 6-SNP system. Both SNPs are highly variable in Europe, where the majority of variation in iris color originates. In the present study, we explore the SNP variation present in the genetic regions of OCA2-HERC2 as well as possible haplotypes. Our research centers around the functional haplotype and the addition of SNPs to the functional haplotype. In addition, three different ways of classifying the phenotype are assessed simultaneously. First, using a 4-point categorical phenotype—blue/blue grey, blue/green yellow, hazel/light brown, and dark brown. Second, calculating a continuous scale from a quantitative phenotype in which the percentage of each categorical color has been measured. Third, using the IrisPlex 6-SNP system to predict eye color and identify individuals which have been inaccurately predicted. Exploration of the SNP and haplotype variation resulted in two SNPs for both the categorical and quantitative phenotypes which were significantly correlated with hazel/light brown—rs1448484 and rs61335644, both as independent SNPs and when assessed in a haplotype with rs1800407-rs12913832. SNP rs1448484 has been associated with skin pigmentation previously and is located in a possible transcription factor binding site. SNP rs61335644 is not presently associated with pigmentation but is in complete LD with two SNPs in and around regulatory regions present in HERC2. Finally, the addition of rs1448484 and rs61335644 into the current IrisPlex 6-SNP system slightly improved each of the tested performance metrics for hazel/light brown and dark brown. Within the inaccurately predicted phenotypes, rs1800407 is confirmed to affect both inaccurately predicted groups and is the most significant SNP. Additionally, rs121918166, a missense variant in OCA2, is the second most significant SNP in true blue predicted as brown. Both SNPs were also the two most significant haplotypes with at least one allele being derived. Therefore, the next steps should include the addition of the functional haplotype and rs121918166 into the current IrisPlex model, and further testing of rs1448484 and rs61335644 on a molecular level. Consequently, the current IrisPlex model should also be reassessed on an independent test set using the 4-point categorical scale rather than the present 3-point scale.
364

SNP / Slovak National Uprising

Orság, Michal January 2014 (has links)
The aim of the thesis was to bring events after 1945, when there was a period of remembrance in the company , which served as a therapy , politics and aesthetics . Work on the memories gradually morphed into , among other things , to the monuments that act against collective oblivion . Arise place of remembrance , which relate to historical events and private stories . Partisan monuments fill in the country which they have to remind essentially absent . Again remembering you and gets to the surface again forgotten information that creating a logical connection form the structure . This structure is subject to change , which helped by rewriting and overlapping information in different layers of the structure . Neither art does not avoid the remembrance and forgetting , and creates a theme of a strategy , which is included rewriting . Media and individual override blank sheets in the past, currently , collecting and composing the mosaic , which allows you to create your own identity.
365

Bayesian Lasso for Detecting Rare Genetic Variants Associated with Common Diseases

Zhou, Xiaofei 23 October 2019 (has links)
No description available.
366

Variant Detection Using Next Generation Sequencing Data

Pyon, Yoon Soo 08 March 2013 (has links)
No description available.
367

Correlations in Genetic Risk Scores Produced by Direct-to-Consumer Genetic Testing Companies

Reys, Brian D. 17 October 2013 (has links)
No description available.
368

Computational Analysis of the Evolution of Non-Coding Genomic Sequences

Saha Mandal, Arnab 21 August 2013 (has links)
No description available.
369

Usage and Development of Molecular Markers for Investigation of the Population and Ecological Genetics of <em>Bromus tectorum</em> L.

Merrill, Keith R. 16 March 2011 (has links) (PDF)
This thesis includes two studies: The first examined patterns of neutral genetic diversity within Bromus tectorum L. across the IMW region, and uses patterns of microsatellite (SSR) genotype distribution to make inferences about the respective roles of adaptively significant genetic variation, adaptive phenotypic plasticity, and facultative outcrossing in the ongoing invasion and recent range expansion of B. tectorum. It has been previously demonstrated that, due to extremely low outcrossing rates, it is possible to characterize individual genotypes of this species using four SSR loci. We sampled 20 individuals from each of 96 B. tectorum populations (classified by region and habitat) from throughout the IMW and used these SSR markers to characterize each individual. We found 131 four-locus SSR genotypes; however, the 14 most common genotypes collectively accounted for 79.2% of the individuals sampled. Individuals with certain SSR genotypes sorted strongly into warm or salt desert habitats (stringent habitats) and flowered earlier than individuals with genotypes from more mesic habitats, providing evidence of adaptively significant genetic variation associated with these genotypes. Other SSR genotypes were found across a wide range of habitats though they tended to be less prevalent in stringent habitats, providing evidence that adaptive phenotypic plasticity may be important for the distribution of some common genotypes. We observed very few heterozygous individuals, consistent with the highly inbreeding reproductive strategy of B. tectorum. Because specialist genotypes dominating recently invaded areas within the IMW region contained unique alleles, they are not likely to have resulted from recombination, leading us to doubt the role of facultative outcrossing as a significant mechanism facilitating the current range expansion of B. tectorum in the IMW.Previous research investigating the population and ecological genetics of Bromus tectorum L. in the North American invaded range has relied on either allozyme or microsatellite (SSR) genetic analyses, both of which have proven to have shortcomings. In order to overcome the issues associated with these other marker types, in the second study of this thesis we developed single nucleotide polymorphism (SNP) markers for B. tectorum by 1) obtaining normalized cDNA, 2) sequencing normalized cDNA using 454 sequencing, 3) aligning resultant contigs and looking for SNPs, 4) designing assays for SNP validation and genotyping using KASPar, 5) converting working KASPar assays for use with the Fluidigm EP1 platform using the 96.96 Dynamic ArrayTM IFC. Sequencing resulted in 1258041 reads, which assembled into 65486 contigs (20782 large contigs exceeding 500 base pairs). Using selection criteria of at least 10x coverage and 30% of the minor allele, 3333 putative SNPs were identified. We developed KASP assays for 255 putative SNPs, which resulted in 101 working polymorphic assays. Ninety-six assays were then successfully converted for use with KASP on the Fluidigm EP1 genotyping platform using 96.96 dynamic arrays.
370

Oat SNP Marker Discovery and Mapping Based on 454 Pyrosequencing of Genome-Reduced <em>Avena magna</em> Murphy <em>et</em> Terrell

Redman, Rachel Rebecca 15 July 2011 (has links) (PDF)
The size and complexity of the oat genomes (Avena L., x = 7) have made genetic studies, including the discovery of molecular markers, difficult. Recent attention to these species has resulted in the development of many DArT -based markers in the tetraploid A. magna Murphy et Terrill (2n = 28, CCDD genomes), along with numerous RFLP's, SSR's, DArT's, and EST-based SNPs in hexaploid A. sativa L. (2n = 42, AACCDD). Here we report the first SNP markers for tetraploid oat based on genome reduction and high-throughput pyrosequencing in two inbred lines of A. magna: A-169 (wild) and Ba 13-13 (domesticated). Initially, the genomes were reduced using restriction digests with EcoRI and BfaI and sequenced to produce 706,426 reads for both genotypes that were subsequently assembled into 57,048 contigs with an average read length of 345 bp. Comparisons of the contigs between the two lines resulted in the detection of 31,304 in silico SNPs. High Resolution Melt (HRM) and KASPar assays were used to validate 1,108 of these in silico SNPs across a panel of diploid, tetraploid, and hexaploid oats. Of the assays, 119 were validated using HRM and 384 using KASPar genotyping in the Fluidigm EP1 system. Both sets of assays were then mapped on a population of 117 F2:8 recombinant inbred lines (RILs) developed from the A-169 x Ba 13-13 cross. A map of the A. magna genome was then constructed. The markers and map provide a new set of genomic tools for tetraploid and hexaploid oat breeding and allow for tracking of genes controlling traits of economic importance and other interesting genes through the evolution of Avena.

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