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Full-Text Articles in Genetics and Genomics

Semantics In Support Of Biodiversity Knowledge Discovery: An Introduction To The Biological Collections Ontology And Related Ontologies, Ramona L. Walls, John Deck, Robert Guralnick, Steve Baskauf, Reed Beaman, Stanley Blum, Shaun Bowers Jan 2014

Semantics In Support Of Biodiversity Knowledge Discovery: An Introduction To The Biological Collections Ontology And Related Ontologies, Ramona L. Walls, John Deck, Robert Guralnick, Steve Baskauf, Reed Beaman, Stanley Blum, Shaun Bowers

Computer Science Faculty Scholarship

The study of biodiversity spans many disciplines and includes data pertaining to species distributions and abundances, genetic sequences, trait measurements, and ecological niches, complemented by information on collection and measurement protocols. A review of the current landscape of metadata standards and ontologies in biodiversity science suggests that existing standards such as the Darwin Core terminology are inadequate for describing biodiversity data in a semantically meaningful and computationally useful way. Existing ontologies, such as the Gene Ontology and others in the Open Biological and Biomedical Ontologies (OBO) Foundry library, provide a semantic structure but lack many of the necessary terms to …


Fusarium Head Blight Resistance And Agronomic Performance In Soft Red Winter Wheat Populations, Daniela Sarti Dvorjak Jan 2014

Fusarium Head Blight Resistance And Agronomic Performance In Soft Red Winter Wheat Populations, Daniela Sarti Dvorjak

Theses and Dissertations--Plant and Soil Sciences

Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schwein.(Petch)], is recognized as one of the most destructive diseases of wheat (Triticum aestivum L. and T. durum L.) and barley (Hordeum vulgare L.) worldwide. Breeding for FHB resistance must be accompanied by selection for desirable agronomic traits. Donor parents with two FHB resistance quantitative trait loci (QTL) Fhb1 (chromosome 3BS) and QFhs.nau-2DL (chromosome 2DL) were crossed to four adapted SRW wheat lines to generate backcross and forward cross progeny. F2 individuals were genotyped and assigned to 4 different groups according to presence/ absence of …


Methods For Integrative Analysis Of Genomic Data, Paul Manser Jan 2014

Methods For Integrative Analysis Of Genomic Data, Paul Manser

Theses and Dissertations

In recent years, the development of new genomic technologies has allowed for the investigation of many regulatory epigenetic marks besides expression levels, on a genome-wide scale. As the price for these technologies continues to decrease, study sizes will not only increase, but several different assays are beginning to be used for the same samples. It is therefore desirable to develop statistical methods to integrate multiple data types that can handle the increased computational burden of incorporating large data sets. Furthermore, it is important to develop sound quality control and normalization methods as technical errors can compound when integrating multiple genomic …


Time-Dependent Random Effect Poisson Random Field Model For Polymorphism Within And Between Two Related Species, Shilei Zhou Dec 2013

Time-Dependent Random Effect Poisson Random Field Model For Polymorphism Within And Between Two Related Species, Shilei Zhou

UNLV Theses, Dissertations, Professional Papers, and Capstones

Molecular evolution is partially driven by mutation, selection, random genetic drift, or combination of the three factors. To quantify the magnitude of these genetic forces, a previously developed time-dependent fixed effect Poisson random field model provides powerful likelihood and Bayesian estimates of mutation rate, selection coefficient, and species divergence time. The assumption of the fixed effect model that selection intensity is constant within a genetic locus but varies across genes is obviously biologically unrealistic, but it serves the original purpose of making statistical inference about selection and divergence between two related species they are individually at mutation-selection-drift inequilibrium. By relaxing …


Hypothesis Driven Single Nucleotide Polymorphism Search (Hydn-Snp-S), Rebecca J. Swett, Angela Elias, Jeffrey A. Miller, Gregory E. Dyson, G. AndréS Cisneros Sep 2013

Hypothesis Driven Single Nucleotide Polymorphism Search (Hydn-Snp-S), Rebecca J. Swett, Angela Elias, Jeffrey A. Miller, Gregory E. Dyson, G. AndréS Cisneros

Chemistry Faculty Research Publications

The advent of complete-genome genotyping across phenotype cohorts has provided a rich source of information for bioinformaticians. However the search for SNPs from this data is generally performed on a study-by-study case without any specific hypothesis of the location for SNPs that are predictive for the phenotype. We have designed a method whereby very large SNP lists (several gigabytes in size), combining several genotyping studies at once, can be sorted and traced back to their ultimate consequence in protein structure. Given a working hypothesis, researchers are able to easily search whole genome genotyping data for SNPs that link genetic locations …


Carcinogenic Adducts Induce Distinct Dna Polymerase Binding Orientations, Kyle B. Vrtis, Radoslaw P. Markiewicz, Louis J. Romano, David Rueda Jun 2013

Carcinogenic Adducts Induce Distinct Dna Polymerase Binding Orientations, Kyle B. Vrtis, Radoslaw P. Markiewicz, Louis J. Romano, David Rueda

Chemistry Faculty Research Publications

DNA polymerases must accurately replicate DNA to maintain genome integrity. Carcinogenic adducts, such as 2-aminofluorene (AF) and N-acetyl-2-aminofluorene (AAF), covalently bind DNA bases and promote mutagenesis near the adduct site. The mechanism by which carcinogenic adducts inhibit DNA synthesis and cause mutagenesis remains unclear. Here, we measure interactions between a DNA polymerase and carcinogenic DNA adducts in real-time by single-molecule fluorescence. We find the degree to which an adduct affects polymerase binding to the DNA depends on the adduct location with respect to the primer terminus, the adduct structure and the nucleotides present in the solution. Not only do the …


Assessing Methods For Assigning Snps To Genes In Gene-Based Tests Of Association Using Common Variants, Ashley Petersen, Carolina Alvarez, Scott Declaire, Nathan L. Tintle May 2013

Assessing Methods For Assigning Snps To Genes In Gene-Based Tests Of Association Using Common Variants, Ashley Petersen, Carolina Alvarez, Scott Declaire, Nathan L. Tintle

Faculty Work Comprehensive List

Gene-based tests of association are frequently applied to common SNPs (MAF>5%) as an alternative to single-marker tests. In this analysis we conduct a variety of simulation studies applied to five popular gene-based tests investigating general trends related to their performance in realistic situations. In particular, we focus on the impact of non-causal SNPs and a variety of LD structures on the behavior of these tests. Ultimately, we find that non-causal SNPs can significantly impact the power of all gene-based tests. On average, we find that the “noise” from 6–12 non-causal SNPs will cancel out the “signal” of one causal …


An Alternative Ribozyme For The Rna Hypercycle, Ishak Elkhal May 2013

An Alternative Ribozyme For The Rna Hypercycle, Ishak Elkhal

Student Research Symposium

In the quest to forward understanding of the prebiotic world (specifically, the RNA World Hypothesis), one of the most interesting paradigms to consider is the potential for cooperative networks that may have driven molecular evolution forward. Such a network may exist as an RNA hypercycle, as proposed by Eigen (1977). Much progress has been made towards an RNA hypercycle-like system, especially using the Azoarcus ribozyme system demonstrated by Vaidya et al. (2012). The current work is dedicated to constructing a second model as a cooperative RNA network, utilizing a group I intron from Coxiella burnetii (Cbu1917). The intron was constructed …


The Torsion Angle Of Random Walks, Mu He May 2013

The Torsion Angle Of Random Walks, Mu He

Masters Theses & Specialist Projects

In this thesis, we study the expected mean of the torsion angle of an n-step
equilateral random walk in 3D. We consider the random walk is generated within a confining sphere or without a confining sphere: given three consecutive vectors →e1 , →e2 , and →e3 of the random walk then the vectors →e1 and →e2 define a plane and the vectors →e2 and →e3 define a second plane. The angle between the two planes is called the torsion angle of the three vectors. Algorithms are …


An Automatic Framework For Embryonic Localization Using Edges In A Scale Space, Zachary Bessinger May 2013

An Automatic Framework For Embryonic Localization Using Edges In A Scale Space, Zachary Bessinger

Masters Theses & Specialist Projects

Localization of Drosophila embryos in images is a fundamental step in an automatic computational system for the exploration of gene-gene interaction on Drosophila. Contour extraction of embryonic images is challenging due to many variations in embryonic images. In the thesis work, we develop a localization framework based on the analysis of connected components of edge pixels in a scale space. We propose criteria to select optimal scales for embryonic localization. Furthermore, we propose a scale mapping strategy to compress the range of a scale space in order to improve the efficiency of the localization framework. The effectiveness of the proposed …


Geometric Framework For Evaluating Rare Variant Tests Of Association, Keli Liu, Shannon Fast, Matthew Zawistowski, Nathan L. Tintle May 2013

Geometric Framework For Evaluating Rare Variant Tests Of Association, Keli Liu, Shannon Fast, Matthew Zawistowski, Nathan L. Tintle

Faculty Work Comprehensive List

The wave of next-generation sequencing data has arrived. However, many questions still remain about how to best analyze sequence data, particularly the contribution of rare genetic variants to human disease. Numerous statistical methods have been proposed to aggregate association signals across multiple rare variant sites in an effort to increase statistical power; however, the precise relation between the tests is often not well understood. We present a geometric representation for rare variant data in which rare allele counts in case and control samples are treated as vectors in Euclidean space. The geometric framework facilitates a rigorous classification of existing rare …


Optimal Methods For Using Posterior Probabilities In Association Testing, Keli Liu, Alexander Luedtke, Nathan L. Tintle May 2013

Optimal Methods For Using Posterior Probabilities In Association Testing, Keli Liu, Alexander Luedtke, Nathan L. Tintle

Faculty Work Comprehensive List

Objective: The use of haplotypes to impute the genotypes of unmeasured single nucleotide variants continues to rise in popularity. Simulation results suggest that the use of the dosage as a one-dimensional summary statistic of imputation posterior probabilities may be optimal both in terms of statistical power and computational efficiency; however, little theoretical understanding is available to explain and unify these simulation results. In our analysis, we provide a theoretical foundation for the use of the dosage as a one-dimensional summary statistic of genotype posterior probabilities from any technology. Methods: We analytically evaluate the dosage, mode and the more general set …


A Polyglot Approach To Bioinformatics Data Integration: Phylogenetic Analysis Of Hiv-1, Steven Reisman, Catherine Putonti, George K. Thiruvathukal, Konstantin Läufer Apr 2013

A Polyglot Approach To Bioinformatics Data Integration: Phylogenetic Analysis Of Hiv-1, Steven Reisman, Catherine Putonti, George K. Thiruvathukal, Konstantin Läufer

Computer Science: Faculty Publications and Other Works

RNA-interference has potential therapeutic use against HIV-1 by targeting highly-functional mRNA sequences that contribute to the virulence of the virus. Empirical work has shown that within cell lines, all of the HIV-1 genes are affected by RNAi-induced gene silencing. While promising, inherent in this treatment is the fact that RNAi sequences must be highly specific. HIV, however, mutates rapidly, leading to the evolution of viral escape mutants. In fact, such strains are under strong selection to include mutations within the targeted region, evading the RNAi therapy and thus increasing the virus’ fitness in the host. Taking a phylogenetic approach, we …


Assessing The Impact Of Differential Genotyping Errors On Rare Variant Tests Of Association, Morgan Mayer-Jochimsen, Shannon Fast, Nathan L. Tintle Mar 2013

Assessing The Impact Of Differential Genotyping Errors On Rare Variant Tests Of Association, Morgan Mayer-Jochimsen, Shannon Fast, Nathan L. Tintle

Faculty Work Comprehensive List

Genotyping errors are well-known to impact the power and type I error rate in single marker tests of association. Genotyping errors that happen according to the same process in cases and controls are known as non-differential genotyping errors, whereas genotyping errors that occur with different processes in the cases and controls are known as differential genotype errors. For single marker tests, non-differential genotyping errors reduce power, while differential genotyping errors increase the type I error rate. However, little is known about the behavior of the new generation of rare variant tests of association in the presence of genotyping errors. In …


Characterization Of The Heart Transcriptome Of The White Shark (Carcharodon Carcharias), Vincent P. Richards, Haruo Suzuki, Michael J. Stanhope, Mahmood S. Shivji Jan 2013

Characterization Of The Heart Transcriptome Of The White Shark (Carcharodon Carcharias), Vincent P. Richards, Haruo Suzuki, Michael J. Stanhope, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Articles

Background: The white shark (Carcharodon carcharias) is a globally distributed, apex predator possessing physical, physiological, and behavioral traits that have garnered it significant public attention. In addition to interest in the genetic basis of its form and function, as a representative of the oldest extant jawed vertebrate lineage, white sharks are also of conservation concern due to their small population size and threat from overfishing. Despite this, surprisingly little is known about the biology of white sharks, and genomic resources are unavailable. To address this deficit, we combined Roche-454 and Illumina sequencing technologies to characterize the first …


Development Of 11 Polymorphic Microsatellite Markers For Xylocarpus Granatum (Meliaceae) Using Next-Generation Sequencing Technology, Yuki Tomizawa, Yoshimi Shinmura, Alison K S Wee, Koji Takayama, Takeshi Asakawa, Orlex Baylen Yllano, Severino G. Salmo Iii, Erwin Riyanto Ardli, Nguyen Xuan Tung, Norhaslinda Binti Malekal, Onrizal Onrizal, Sankararamasubramanian H. Meenakshisundaram, Sarawood Sungkaew, Mohd Nazre Saleh, Bayu Adjie, Khin Khin Soe, Emiko Oguri, Noriaki Murakami, Yasuyuki Watano, Shigeyuki Baba, Edward L. Webb, Tadashi Kajita Jan 2013

Development Of 11 Polymorphic Microsatellite Markers For Xylocarpus Granatum (Meliaceae) Using Next-Generation Sequencing Technology, Yuki Tomizawa, Yoshimi Shinmura, Alison K S Wee, Koji Takayama, Takeshi Asakawa, Orlex Baylen Yllano, Severino G. Salmo Iii, Erwin Riyanto Ardli, Nguyen Xuan Tung, Norhaslinda Binti Malekal, Onrizal Onrizal, Sankararamasubramanian H. Meenakshisundaram, Sarawood Sungkaew, Mohd Nazre Saleh, Bayu Adjie, Khin Khin Soe, Emiko Oguri, Noriaki Murakami, Yasuyuki Watano, Shigeyuki Baba, Edward L. Webb, Tadashi Kajita

Environmental Science Faculty Publications

Human impacts have seriously damaged mangroves, and conservation of mangroves will require information on local and regional population genetic structures. Here, we report the development and polymorphism of eleven novel microsatellite markers, developed using next- generation sequencing on 56 samples of widespread man- grove species Xylocarpus granatum (Meliaceae) from nine populations across the Indo-West Pacific region. All loci were found to be polymorphic, with the number of alleles per locus ranging from four to 19. In a population from Sabah (Malaysia), the mean observed and expected heterozygosity per locus was 0.59 and 0.58, respectively. No null allele, significant linkage disequilibrium …


Next-Peak: A Normal-Exponential Two-Peak Model For Peak-Calling In Chip-Seq Data, Nak-Kyeong Kim, Rasika V. Jayatillake, John L. Spouge Jan 2013

Next-Peak: A Normal-Exponential Two-Peak Model For Peak-Calling In Chip-Seq Data, Nak-Kyeong Kim, Rasika V. Jayatillake, John L. Spouge

Mathematics & Statistics Faculty Publications

Background: Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) can locate transcription factor binding sites on genomic scale. Although many models and programs are available to call peaks, none has dominated its competition in comparison studies.

Results: We propose a rigorous statistical model, the normal-exponential two-peak (NEXT-peak) model, which parallels the physical processes generating the empirical data, and which can naturally incorporate mappability information. The model therefore estimates total strength of binding (even if some binding locations do not map uniquely into a reference genome, effectively censoring them); it also assigns an error to an estimated binding location. The comparison study …


Image-Level And Group-Level Models For Drosophila Gene Expression Pattern Annotation, Quian Sun, Sherin Muckatira, Lei Yuan, Shuiwang Ji, Stuart Newfeld, Sudhir Kumar, Jieping Ye Jan 2013

Image-Level And Group-Level Models For Drosophila Gene Expression Pattern Annotation, Quian Sun, Sherin Muckatira, Lei Yuan, Shuiwang Ji, Stuart Newfeld, Sudhir Kumar, Jieping Ye

Computer Science Faculty Publications

Background: Drosophila melanogaster has been established as a model organism for investigating the developmental gene interactions. The spatio-temporal gene expression patterns of Drosophila melanogaster can be visualized by in situ hybridization and documented as digital images. Automated and efficient tools for analyzing these expression images will provide biological insights into the gene functions, interactions, and networks. To facilitate pattern recognition and comparison, many web-based resources have been created to conduct comparative analysis based on the body part keywords and the associated images. With the fast accumulation of images from high-throughput techniques, manual inspection of images will impose a serious impediment …


Pronounced Genetic Structure In A Highly Mobile Coral Reef Fish, Caesio Cuning, In The Coral Triangle, Amanda S. Ackiss, Shinta Pardede, Eric D. Crandall, Ma Carmen A. Ablan-Lagman, Ambariyanto, November Romena, Paul H. Barber, Kent E. Carpenter Jan 2013

Pronounced Genetic Structure In A Highly Mobile Coral Reef Fish, Caesio Cuning, In The Coral Triangle, Amanda S. Ackiss, Shinta Pardede, Eric D. Crandall, Ma Carmen A. Ablan-Lagman, Ambariyanto, November Romena, Paul H. Barber, Kent E. Carpenter

Biological Sciences Faculty Publications

The redbelly yellowtail fusilier Caesio cuning has a tropical Indo-West Pacific range that straddles the Coral Triangle, a region of dynamic geological history and the highest marine biodiversity on the planet. Previous genetic studies in the Coral Triangle indicate the presence of multiple limits to connectivity. However, these studies have focused almost exclusively on benthic, reef-dwelling species. Schooling, reef-associated fusiliers (Perciformes: Caesionidae) account for a sizable portion of the annual reef catch in the Coral Triangle, yet to date, there have been no indepth studies on the population structure of fusiliers or other mid-water, reef-associated planktivores across this region. We …


A Novel Computational Framework For Transcriptome Analysis With Rna-Seq Data, Yin Hu Jan 2013

A Novel Computational Framework For Transcriptome Analysis With Rna-Seq Data, Yin Hu

Theses and Dissertations--Computer Science

The advance of high-throughput sequencing technologies and their application on mRNA transcriptome sequencing (RNA-seq) have enabled comprehensive and unbiased profiling of the landscape of transcription in a cell. In order to address the current limitation of analyzing accuracy and scalability in transcriptome analysis, a novel computational framework has been developed on large-scale RNA-seq datasets with no dependence on transcript annotations. Directly from raw reads, a probabilistic approach is first applied to infer the best transcript fragment alignments from paired-end reads. Empowered by the identification of alternative splicing modules, this framework then performs precise and efficient differential analysis at automatically detected …


Innovative Applications Of Genetic Algorithms To Problems In Accelerator Physics, Alicia Hofler, Balša Terzić, Matthew Kramer, Anton Zvezdin, Vasiliy Morozov, Yves Roblin, Fanglei Lin, Colin Jarvis Jan 2013

Innovative Applications Of Genetic Algorithms To Problems In Accelerator Physics, Alicia Hofler, Balša Terzić, Matthew Kramer, Anton Zvezdin, Vasiliy Morozov, Yves Roblin, Fanglei Lin, Colin Jarvis

Physics Faculty Publications

The genetic algorithm (GA) is a powerful technique that implements the principles nature uses in biological evolution to optimize a multidimensional nonlinear problem. The GA works especially well for problems with a large number of local extrema, where traditional methods (such as conjugate gradient, steepest descent, and others) fail or, at best, underperform. The field of accelerator physics, among others, abounds with problems which lend themselves to optimization via GAs. In this paper, we report on the successful application of GAs in several problems related to the existing Continuous Electron Beam Accelerator Facility nuclear physics machine, the proposed Medium-energy Electron-Ion …


Contour Extraction Of Drosophila Embryos Using Active Contours In Scale Space, Soujanya Siddavaram Ananta Dec 2012

Contour Extraction Of Drosophila Embryos Using Active Contours In Scale Space, Soujanya Siddavaram Ananta

Masters Theses & Specialist Projects

Contour extraction of Drosophila embryos is an important step to build a computational system for pattern matching of embryonic images which aids in the discovery of genes. Automatic contour extraction of embryos is challenging due to several image variations such as size, shape, orientation and neigh- boring embryos such as touching and non-touching embryos. In this thesis, we introduce a framework for contour extraction based on the connected components in the gaussian scale space of an embryonic image. The active contour model is applied on the images to refine embryo contours. Data cleaning methods are applied to smooth the jaggy …


Reconstructability Analysis Of Genetic Loci Associated With Alzheimer Disease, Martin Zwick, Shawn K. Westaway, Stephen Shervais, Patricia L. Kramer Nov 2012

Reconstructability Analysis Of Genetic Loci Associated With Alzheimer Disease, Martin Zwick, Shawn K. Westaway, Stephen Shervais, Patricia L. Kramer

Complex Systems Faculty Publications and Presentations

Reconstructability Analysis (RA) is an information- and graph-theory-based method which has been successfully used in previous genomic studies. Here we apply it to genetic (14 SNPs) and non-genetic (Education, Age, Gender) data on Alzheimer disease in a well-characterized Case/Control sample of 424 individuals. We confirm the importance of APOE as a predictor of the disease, and identify one non-genetic factor, Education, and two SNPs, one in BINI and the other in SORCS1, as likely disease predictors. SORCS1 appears to be a common risk factor for people with or without APOE. We also identify a possible interaction effect between Education and …


Phylogenetics Links Monster Larva To Deep-Sea Shrimp., Heather D Bracken-Grissom, Darryl L Felder, Nicole L Vollmer, Joel W Martin, Keith A Crandall Oct 2012

Phylogenetics Links Monster Larva To Deep-Sea Shrimp., Heather D Bracken-Grissom, Darryl L Felder, Nicole L Vollmer, Joel W Martin, Keith A Crandall

Computational Biology Institute

Mid-water plankton collections commonly include bizarre and mysterious developmental stages that differ conspicuously from their adult counterparts in morphology and habitat. Unaware of the existence of planktonic larval stages, early zoologists often misidentified these unique morphologies as independent adult lineages. Many such mistakes have since been corrected by collecting larvae, raising them in the lab, and identifying the adult forms. However, challenges arise when the larva is remarkably rare in nature and relatively inaccessible due to its changing habitats over the course of ontogeny. The mid-water marine species Cerataspis monstrosa (Gray 1828) is an armored crustacean larva whose adult identity …


Development And Characterization Of 11 Novel Microsatellite Loci For The Roundscale Spearfish Tetrapturus Georgii And Their Cross-Species Amplification Among Other Istiophorid Species, Andrea M. Bernard, Kevin A. Feldheim, Mahmood S. Shivji Oct 2012

Development And Characterization Of 11 Novel Microsatellite Loci For The Roundscale Spearfish Tetrapturus Georgii And Their Cross-Species Amplification Among Other Istiophorid Species, Andrea M. Bernard, Kevin A. Feldheim, Mahmood S. Shivji

Marine & Environmental Sciences Faculty Articles

Eleven novel polymorphic microsatellite loci were developed and characterized for the recently validated roundscale spearfish Tetrapturus georgii. Characterization of these markers, based on 35 roundscale spearfish from the western North Atlantic, revealed two to 21 alleles per locus with an average expected heterozygosity (HE) of 0·09–0·94, and all loci conformed to Hardy–Weinberg expectations. Cross-amplification of these 11 loci against all other eight known istiophorid species indicates promising prospects for the utility of these markers for istiophorids in general.


Genetic Susceptibility To Type 2 Diabetes: A Global Meta-Analysis Studying The Genetic Differences In Tunisian Populations, Rym Berhouma, S. Kouidhi, M. Ammar, H. Abid, T. Baroudi, H. Ennafaa, A. Benammar-Elgaaied Aug 2012

Genetic Susceptibility To Type 2 Diabetes: A Global Meta-Analysis Studying The Genetic Differences In Tunisian Populations, Rym Berhouma, S. Kouidhi, M. Ammar, H. Abid, T. Baroudi, H. Ennafaa, A. Benammar-Elgaaied

Human Biology Open Access Pre-Prints

The present study is the first meta-analysis to evaluate type 2 diabetes (T2D) - associated polymorphisms in cohorts originated from several Tunisian regions. In fact, we evaluated the effect of seven polymorphisms in the following genes; PPARg ( Pro12Ala), TNFα (-308A/G), ENPP1(K121Q), TCF7L2(rs7903146 C/T), MTHFR( C677T), ACE(I/D), CAPN10(3R/2R) on T2D risk, through a meta-analysis combining data of previous studies performed on Tunisian populations originating from the north, centre or south of the country. R statistics version 2.12.1 software was used to estimate the heterogeneity between studies. Pooled ORs were computed by the fixed-effects method of Mantel-Haenszel if no heterogeneity between …


Dna Methylation Arrays As Surrogate Measures Of Cell Mixture Distribution, Eugene Houseman, William P. Accomando, Devin C. Koestler, Brock C. Christensen, Carmen J. Marsit May 2012

Dna Methylation Arrays As Surrogate Measures Of Cell Mixture Distribution, Eugene Houseman, William P. Accomando, Devin C. Koestler, Brock C. Christensen, Carmen J. Marsit

Dartmouth Scholarship

There has been a long-standing need in biomedical research for a method that quantifies the normally mixed composition of leukocytes beyond what is possible by simple histological or flow cytometric assessments. The latter is restricted by the labile nature of protein epitopes, requirements for cell processing, and timely cell analysis. In a diverse array of diseases and following numerous immune-toxic exposures, leukocyte composition will critically inform the underlying immuno-biology to most chronic medical conditions. Emerging research demonstrates that DNA methylation is responsible for cellular differentiation, and when measured in whole peripheral blood, serves to distinguish cancer cases from controls.


Why Odds Ratio Estimates Of Gwas Are Almost Always Close To 1.0, Yutaka Yasui May 2012

Why Odds Ratio Estimates Of Gwas Are Almost Always Close To 1.0, Yutaka Yasui

COBRA Preprint Series

“Missing heritability” in genome-wide association studies (GWAS) refers to the seeming inability for GWAS data to capture the great majority of genetic causes of a disease in comparison to the known degree of heritability for the disease, in spite of GWAS’ genome-wide measures of genetic variations. This paper presents a simple mathematical explanation for this phenomenon, assuming that the heritability information exists in GWAS data. Specifically, it focuses on the fact that the great majority of association measures (in the form of odds ratios) from GWAS are consistently close to the value that indicates no association, explains why this occurs, …


A Streamlined Dna Tool For Global Identification Of Heavily Exploited Coastal Shark Species (Genus Rhizoprionodon), D. Pinhal, Mahmood S. Shivji, Pedro G. Nachtigall, Demian D. Chapman, Cesar Martins Apr 2012

A Streamlined Dna Tool For Global Identification Of Heavily Exploited Coastal Shark Species (Genus Rhizoprionodon), D. Pinhal, Mahmood S. Shivji, Pedro G. Nachtigall, Demian D. Chapman, Cesar Martins

Marine & Environmental Sciences Faculty Articles

Obtaining accurate species-specific landings data is an essential step toward achieving sustainable shark fisheries. Globally distributed sharpnose sharks (genus Rhizoprionodon) exhibit life-history characteristics (rapid growth, early maturity, annual reproduction) that suggests that they could be fished in a sustainable manner assuming an investment in monitoring, assessment and careful management. However, obtaining species-specific landings data for sharpnose sharks is problematic because they are morphologically very similar to one another. Moreover, sharpnose sharks may also be confused with other small sharks (either small species or juveniles of large species) once they are processed (i.e., the head and fins are removed). Here …


Modeling The Dispersion Of Eastern Oyster Larvae (Crassostrea Virginica) And Its Effects On The Movement Of Disease Resistant Genes In The Delaware Bay Estuary, Diego A. Narvaez Apr 2012

Modeling The Dispersion Of Eastern Oyster Larvae (Crassostrea Virginica) And Its Effects On The Movement Of Disease Resistant Genes In The Delaware Bay Estuary, Diego A. Narvaez

OES Theses and Dissertations

This study combines several models to address two primary research questions. How does the interaction of larval biology and environmental variability determine the spatial distribution of oyster larvae in Delaware Bay? What is the role of larval dispersion in the transference of disease-resistant genes? The particle-tracking module in the Regional Ocean Modeling System (ROMS) was converted into an Individual-Based model representing Eastern oyster larvae that has growth and vertical migration. Exchange of larvae between natural oyster reefs was estimated and used in an Individual-Based genetic model that simulates the genetic structure of eastern oysters. Particles were released from a number …