Genetics Commons^™

The Role Of The Virb Ligand Ctp In The Molecular Mechanism Of Transcriptional Anti-Silencing In Shigella Flexneri, Taylor M. Gerson, Monika M A Karney, Helen Wing

Life Sciences Faculty Research

In bacteria, nucleoid-structuring proteins bind and constrain DNA, often leading to transcriptional silencing. In Shigella spp., the histone-like nucleoid-structuring protein H-NS silences many genes on the large virulence plasmid. Upon a shift to human body temperature, VirB, a DNA-binding protein and key transcriptional regulator of the Shigella virulence cascade, is produced. VirB counteracts H-NS-mediated transcriptional silencing and belongs to a fast-evolving clade of the ParB superfamily. Like other ParB proteins, VirB binds the ligand CTP. While CTP is essential for the anti-silencing activity of VirB, the role of CTP in the mechanism of VirB-dependent anti-silencing has yet to be …

Investigating The Influence Of Environmental Stressors To Exopolysaccharide Production In Soil Cyanobacteria: Genomic And Physiological Perspectives, Benjy Sedano-Herrera

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cyanobacteria are photosynthetic microbes with essential roles in Earth’s ecosystems. The secretion of long–chain polysaccharides, known as exopolysaccharides (EPS), is a key trait facilitating cyanobacterial adaptation to diverse ecosystems. Genomics studies have shown that aquatic cyanobacteria harbor multiple gene copies encoding EPS export proteins, likely conferring a selective advantage in lakes or oceans. In addition, physiological experiments showed that nutrient limitation in aquatic habitats influences EPS production, affecting cyanobacterial fitness. However, whether terrestrial cyanobacteria also harbor multiple EPS-related genes and how nutrient limitation impacts their EPS production is not well understood.In the first chapter of my thesis, we investigated the …

Delineating Genetic Influences On Neurodegenerative Disorders And Infectious Diseases Through Advanced Computational Methods, Xiaowei Zhuang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Genetics plays a critical role in understanding the molecular mechanisms underlying neurodegenerative disorders and pathogen evolution in infectious diseases. For example, identifying genetic variants associated with a disease phenotype uncovers functional pathways that could lead to potential drug targets and therapeutic interventions. In addition, tracking the genetic evolution of pathogens enables early detection and warning of infectious disease outbreaks. In both applications, given the large amount of genetic data, advanced computational methods, including longitudinal and multivariate models, could significantly boost the statistical power and capture interrelationships among traits, environmental factors and genetic influences. This dissertation focuses on four applications of …

Glial-Specific Genes Are Strongly Associated With Alzheimer's Disease By Gene-Based Polygenic Risk Score Analysis, Jennifer Zheng, Faria Tavacoli, Tyrell Pratt, Alice Lee, Tingwei Liu, Jingchun Chen

Undergraduate Research Symposium Posters

Methods: Gene-based PRSs were constructed in AD cases and controls within each gene of the glial cells, according to the GWAS summary statistics of European ancestry. In detail, gene-based PRSs were first calculated for each glial cell type-specific gene for AD cases and controls in the discovery dataset (ADc1234ADA) using PRSet software. A meta-analysis with a fixed model was performed when the signal in both datasets was in the same direction. Bonferroni corrections for multiple testing (at α = .05) were used to determine significance within each of the three glial groups. Forest plots were used to visualize the results …

Pathway-Based Polygenic Risk Score Analysis Of Brain Glial Indicates Cell-Type-Specific Roles In Alzheimer's Disease, Tyrell Pratt, Alice Lee, Jennifer Zheng, Faria Tavacoli, Hayley Ho, Tingwei Liu, Jingchun Chen

Undergraduate Research Symposium Posters

Background: Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline and extensive brain pathology, including amyloid plaques, neurofibrillary tangles, and neuroinflammation. This study aims to identify any glial cell type-specific pathways associated with AD.

Methods: We first investigated the correlation between AD and the genetic risk of glia-specific pathways using pathway-based polygenic risk score (PRS) with PRSet software in the discovery data (ADc1234ADA) adjusted by the top two principal components (PC1, PC2) (Model 1), followed by additional adjustment with sex, age, and APOE ε4 count in Model 2. Further PRSet analyses were replicated in independent data …

Disruption Of The Oswrky71 Transcription Factor Gene Results In Early Rice Seed Germination Under Normal And Cold Stress Conditions, Santiago Bataller, James A. Davis, Lingkun Gu, Sophia Baca, Gaelan Chen, Azeem Majid, Anne J. Villacastin, Dylan Barth, Mira V. Han, Paul J. Rushton, Qingxi J. Shen

Life Sciences Faculty Research

Background

Early seed germination in crops can confer a competitive advantage against weeds and reduce the time to maturation and harvest. WRKY transcription factors regulate many aspects of plant development including seed dormancy and germination. Both positive and negative regulators of seed germination have been reported in many plants such as rice and Arabidopsis. Using a transient expression system, we previously demonstrated that OsWRKY71 is a negative regulator of gibberellin (GA) signaling in aleurone cells and likely forms a “repressosome” complex with other transcriptional repressors. Hence, it has the potential to impact seed germination properties.

Results

In this study, we …

Personalized Nutrition: Tailoring Dietary Recommendations Through Genetic Insights, Saiful Singar, Ravinder Nagpal, Bahram H. Arjmandi, Neda S. Akhavan

Kinesiology and Nutrition Sciences Faculty Research

Personalized nutrition (PN) represents a transformative approach in dietary science, where individual genetic profiles guide tailored dietary recommendations, thereby optimizing health outcomes and managing chronic diseases more effectively. This review synthesizes key aspects of PN, emphasizing the genetic basis of dietary responses, contemporary research, and practical applications. We explore how individual genetic differences influence dietary metabolisms, thus underscoring the importance of nutrigenomics in developing personalized dietary guidelines. Current research in PN highlights significant gene–diet interactions that affect various conditions, including obesity and diabetes, suggesting that dietary interventions could be more precise and beneficial if they are customized to genetic profiles. …

A Timeline Of Klinefelter’S Syndrome, Xxy, Emma Chevalier, Tyler Venegas, Mary Salibi

Undergraduate Research Symposium Posters

Klinefelter Syndrome (KS) is a non-mendelian chromosomal disorder consisting of supernumerary X chromosomes in males, 80% of which manifest as the 47,XXY karyotype. The resulting gene dosage abnormalities affect both cognitive and physical development, with variable expressivity. The disease was first described by Harry Klinefelter in 1942 and was thought to be an endocrine disorder until the late 1950s, when karyotyping of affected individuals revealed an extra X chromosome.

(It is the most common sex chromosome aneuploidy (1:500 males) and the most common cause of azoospermia. The phenotype for KS is highly contested due to its extremely variable expressivity and …

A Genetic Screen For Metabolic Modulators In Drosophila Melanogaster, Victoria Campos, Logan Kazimer, Brandon Polimeni, Katelyn Niswonger, Matthew Meiselman

Undergraduate Research Symposium Posters

When environments become unfavorable, to preserve energy, animals will attenuate reproduction and limit growth. This evolutionary strategy requires perceiving and assessing a complex environment, a long-standing role of the nervous system. However, the nervous system’s control over endocrine states remains a monumental challenge. Here, we propose to exploit the genetic accessibility and cellular resolution readily found in Drosophila melanogaster, to fully explore how the brain controls metabolic and reproductive states. This project relies on the Meiselman Lab’s established unbiased neural activation screen, which located new neural circuits that participate in metabolic control. The project proposes the use of the split …

Sequestered Sequences: A Bioinformatic Approach To The Forgotten Genome, Dylan Barth

UNLV Theses, Dissertations, Professional Papers, and Capstones

As high throughput sequencing generates ever increasing amounts of genetic and epigenetic data new lines of inquiry open up in the field of genomic research. In this thesis, we discuss three ways in which we can utilize public databases of next generation genomic data in order to study areas of the genome previously ignored by traditional approaches. These include the study of linker regions between domains of proteins, indirect enhancers that do not strongly contact promoters of genes they regulate, and transposon-derived enhancer elements. The work uncovers many exceptions to known biological principles, and adds nuance to our understanding of …

The Genetic Relationship Between Peripheral Inflammation And Alzheimer’S Disease, Davis Cammann

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is the leading cause of dementia worldwide, and has become an ever-present problem in aging populations. An increasing body of evidence suggests that neuroinflammation is one of the key drivers of AD pathology. One overlooked contributor to this burden is peripheral inflammation throughout the body. Due to increased permeability of the blood-brain-barrier (BBB) in older age, inflammatory plasma proteins and immune cells infiltrate the CNS and drive neuroinflammation through interactions with neurons and glia. In addition, age-related changes in the composition of gut microbiome taxa lead to increased gut permeability and inflammatory burden. Because inflammatory factors are …

Retrospective Varying Coefficient Association Analysis Of Longitudinal Binary Traits, Gang Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many genetic studies contain rich information on longitudinal phenotypes that require powerful analytical tools for optimal analysis. Genetic analysis of longitudinal data that incorporates temporal variation is important for understanding the genetic architecture and biological variation of complex diseases. Most of the existing methods assume that the contribution of genetic variants is constant over time and fails to capture the dynamic pattern of disease progression. However, the relative influence of genetic variants on complex traits fluctuates over time.We developed several tests to fill the gap of analyzing time-varying genetic effects in longitudinal GWAS for binary traits. First, we propose a …

The Utilization Of Crispr/Cas9 In Monogenic Disorders Authors, Shauna M. Mellor

Spectra Undergraduate Research Journal

This paper is a literature review of various scientific research papers, exploring the recent scientific advancement in the field of genetic engineering. The research presented is a foundational tool, building awareness on the implications of CRISPR/ Cas9 technology. CRISPR/ Cas9 was first discovered through the study of bacterial immune systems, fighting against viral infections. Manipulation of the Cas9 protein would eventually lead to target specific, gene-altering medicines for human organisms. CRISPR/ Cas 9 technology has begun to show promise as an effective treatment for certain monogenic disorders. Despite this, time is required before its efficacy as a proven genetic treatment …

Strategic Plan For Genomic Competencies Into Undergraduate Nursing Curriculum, Myerann Royce M. Mangalino

UNLV Theses, Dissertations, Professional Papers, and Capstones

Problem: As genomics research continues to grow in medicine and in popular culture, an educational gap in nursing is inevitable. Nurses must have a strong understanding of genetics and genomics to effectively integrate them into current practice.Objectives: The objective is to identify gaps in the current undergraduate curriculum and build threads that may be incorporated into the current curriculum to fill the identified gaps. Methods: The foundation of this project was the Essentials of Genetic and Genomic Nursing: Competencies, Curricula Guidelines, and Outcome Indicators, 2nd Edition (Consensus Panel on Genetic/Genomic Nursing Competencies, 2008). A strategic plan was created to increase …

Improving Self-Efficacy And Knowledge While Reducing Anxiety In High-Risk Breast Cancer Patients Through Standardized Education, Shelley Miles

UNLV Theses, Dissertations, Professional Papers, and Capstones

Breast cancer is the leading cause of death of women in the United States. Patients at high risk for developing cancer are more easily identified in today’s world. Early identification might be due to strong family history or genetic mutations, such as BRCA1 or BRCA2. Screening and risk reduction guidelines have been developed over recent years for these patients. Adherence to these guidelines continues to be a problem. The factors stemming from this problem include lack of knowledge about being high-risk, understanding the guidelines, and anxiety and depression about the perceived risk of developing breast cancer. These factors can cause …

Increasing Genetic Testing Rates To Improve Early Detection And Prevention Of Breast And Ovarian Cancer In Women, Makensey Beth Durrant

UNLV Theses, Dissertations, Professional Papers, and Capstones

Screening rates for cancer related genetic mutations are low in the primary care setting, despite evidence-based guidelines recommending screening in all patients who meet criteria. Genetic mutations, such as the breast cancer susceptibility 1 and 2 (BRCA1/2) gene mutations, drastically increase breast and ovarian cancer risk in patients. The United States Preventive Services Task Force (USPSTF) and the National Comprehensive Cancer Network (NCCN) provide evidence-based guidelines on criteria for genetic testing in women at risk for breast and ovarian cancer related gene mutations. Primary care providers (PCPs), including advanced practice registered nurses (APRNs), are at the front lines of preventative …

A Screen For Sleep And Starvation Resistance Identifies A Wake-Promoting Role For The Auxiliary Channel Unc79, Kazuma Murakami, Justin Palermo, Bethany A. Stanhope, Allen G. Gibbs, Alex C. Keene

Life Sciences Faculty Research

The regulation of sleep and metabolism are highly interconnected, and dysregulation of sleep is linked to metabolic diseases that include obesity, diabetes, and heart disease. Furthermore, both acute and long-term changes in diet potently impact sleep duration and quality. To identify novel factors that modulate interactions between sleep and metabolic state, we performed a genetic screen for their roles in regulating sleep duration, starvation resistance, and starvation-dependent modulation of sleep. This screen identified a number of genes with potential roles in regulating sleep, metabolism, or both processes. One such gene encodes the auxiliary ion channel UNC79, which was implicated in …

Genomic Analysis Of Paenibacillus Larvae Bacteriophages, Casey Stamereilers

UNLV Theses, Dissertations, Professional Papers, and Capstones

American Foulbrood is the most destructive bacterial infection of the honeybee (Apis mellifera) and is caused by the Gram-positive, spore forming bacterium Paenibacillus larvae. Current treatment methods rely on antibiotics, but antibiotics treatments are experiencing a reduction in efficacy due to the recent rise in antibiotic resistant strains of P. larvae. This has been a major catalyst for exploration of alternative treatment methods. Phage therapy is an alternative treatment method that uses viruses that exclusively infect bacteria, known as bacteriophages (phages), to combat bacterial infections. Several experimental studies have shown that phages P. larvae phages are effective at lysing P. …

A Timeline Of Oculocutaneous Albinism, Mohammed Abushanab, Maria Ceroni, Kimberly Morán

Undergraduate Research Symposium Posters

The purpose of this research timeline is to synthesize the natural history of Oculocutaneous Albinism (OCA), discover gaps in knowledge, as well as understand the genes and mutations that incite the disease. It is through methods of literature-based research that we found the earliest recognition of OCA and investigated it up to its most current state of research. The rate of research remains steady and continuous with the focus varying widely; either by examining more of the genes involved in the disease or by taking more in-depth looks at mutational analyses of genes that are already observed to be linked …

An Investigation On The History And Current Research Of Fragile X Syndrome, Makeda Asare, Isabelle Avenido, Maxene Vergonia-Fehlman

Undergraduate Research Symposium Posters

The purpose of this research is to synthesize the history of Fragile X Syndrome through literature-based research in order to assess the scope of research, population variation, social impact, and treatment. Fragile X was first documented in 1943 by Dr. Julia Bell and Dr. James Purdon Martin in a report of a family case study in which eleven males across two generations showed symptoms of intellectual disabilities. Fragile X Syndrome is an X-linked disorder caused by mutation in the Fragile X mental retardation 1(FMR1) gene on chromosome Xq27.3. The FMR1 mutations are triplet repeat expansion of the CGG repeat sequences …

The History And Future Of Cystic Fibrosis, Randall Combs, Che Fung Andy Chan, Daisy Sahagun

Undergraduate Research Symposium Posters

The purpose of this research timeline is to highlight the tumultuous yet inspiring history of Cystic Fibrosis disease and treatment to give us a more pragmatic understanding of its current state. Cystic Fibrosis is an autosomal recessive disease, most often caused by a single amino-acid deletion of phenylalanine at position 508 in the nucleotide binding domain, which results in a loss of the cystic fibrosis transmembrane conductance regulator (CFTR). Symptomatology varies considerably but a buildup of mucus in the respiratory tract leading to lung failure, and exocrine pancreatic insufficiency which results in digestive and metabolic dysfunction are commonly, if not …

Retinoblastoma: Past, Present, And Future, Izabela Daneva, Crysty-Ann Olaco, Albert Tran

Undergraduate Research Symposium Posters

The purpose of this research timeline is to synthesize the natural history of retinoblastoma to understand its societal effects and develop a public health message to raise awareness of the disease. We used literature-based research in order to gain an understanding about the discovery of this disease and investigate its most current state of knowledge. Retinoblastoma is an intraocular cancer that manifests early in childhood. It is typically linked to a somatic or germline insertion, deletion, or single-base substitution mutation on both alleles of RB1, a tumor-suppressor gene. Retinoblastoma was first identified in 1809 by James Wardrop, and since then, …

Study Of Sickle Cell Disease, Aaron Guevarra, Carlos Herrera, Faysal Ali

Undergraduate Research Symposium Posters

The purpose of this research timeline is to explore the history, prevalence, and effects of Sickle Cell Disease (SCD) so that treatments and possible future experiments or cures may be discussed. In SCD, abnormal red blood cells appear as sickle shaped as opposed to the round shape of normal red blood cells. It is inherited in an autosomal recessive pattern, so an individual must inherit two copies of the allele. The gene mutation is a single nucleotide mutation in the gene which codes for β-globin. In 1910, James B. Herrick first described the disease, and in 1949, its inheritance pattern …

Bayesian Variable Selection Methods For Genome-Wide Association Studies With Categorical Phenotypes, Benazir Rowe

UNLV Theses, Dissertations, Professional Papers, and Capstones

Genome-wide association studies (GWAS) attempt to find the associations between genetic markers and studied traits (phenotypes). The problem of GWAS is complex and various methods have been developed to approach it. One of such methods is Bayesian variable selection (BVS). We describe the BVS methods in detail and demonstrate the ability of BVS method Posterior Inference via Model Averaging and Subset Selection (piMASS) to improve the power of detecting phenotype-associated genetic loci, potentially leading to new discoveries from existing data without increasing the sample size.

We present several ways to improve and extend the applicability of piMASS for GWAS. The …

Identification Of De Novo Mutations In Prenatal Neurodevelopment-Associated Genes In Schizophrenia In Two Han Chinese Patient-Sibling Family-Based Cohorts, Shan Jiang, Daizhan Zhou, Yin-Ying Wang, Peilin Jia, Chunling Wan, Xingwang Li, Guang He, Dongmei Cao, Xiaoqian Jiang, Kenneth S. Kendler, Ming Tsuang, Travis Mize, Jain-Shing Wu, Yimei Lu, Lin He, Jingchun Chen, Zhongming Zhao, Xiangning Chen

School of Medicine Faculty Research

Schizophrenia (SCZ) is a severe psychiatric disorder with a strong genetic component. High heritability of SCZ suggests a major role for transmitted genetic variants. Furthermore, SCZ is also associated with a marked reduction in fecundity, leading to the hypothesis that alleles with large effects on risk might often occur de novo. In this study, we conducted whole-genome sequencing for 23 families from two cohorts with unaffected siblings and parents. Two nonsense de novo mutations (DNMs) in GJC1 and HIST1H2AD were identified in SCZ patients. Ten genes (DPYSL2, NBPF1, SDK1, ZNF595, ZNF718, GCNT2, SNX9, AACS, KCNQ1, and MSI2) were found to …

Transposable Element Expression In Human Embryo Single-Cell Rna-Seq Data, Corinne Sexton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Transposable elements (TEs) are genetic sequences which are mobile within the genome, including DNA transposons and retrotransposons. Though the vast majority are no longer able to move or duplicate in humans, they still are actively transcribed in both germline and somatic cells, particularly in early human development. TEs are expressed in an extremely cell-type and stage specific pattern during embryogenesis, suggesting that they may either have a regulatory role in the cell or be transcribed along with cell-specific genes. However, earlier studies have focused on hESC models or early embryos up to day 6, with differing patterns of TE expression. …

An Investigation Into Multi-View Error Correcting Output Code Classifiers Applied To Organ Tissue Classification, Daniel Alvarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Large amounts of data is being generated constantly each day, so much data that it is difficult to find patterns in order to predict outcomes and make decisions for both humans and machines alike. It would be useful if this data could be simplified using machine learning techniques. For example, biological cell identity is dependent on many factors tied to genetic processes. Such factors include proteins, gene transcription, and gene methylation. Each of these factors are highly complex mechanism with immense amounts of data. Simplifying these can then be helpful in finding patterns in them. Error-Correcting Output Codes (ECOC) does …

Identifying Pleiotropic Snps Associated With Femoral Neck And Heel Bone Mineral Density, Pei He, Xinag-He Ming, Xiao Zhang, Xu Lin, Qiang Zhang, Ri-Li Jiang, Martin R. Schiller, Fei-Yan Deng, Hong-Wen Deng

Life Sciences Faculty Research

Background: Genome-wide association studies (GWASs) routinely identify loci associated with risk factors for osteoporosis. However, GWASs with relatively small sample sizes still lack sufficient power to ascertain the majority of genetic variants with small to modest effect size, which may together truly influence the phenotype. The loci identified only account for a small percentage of the heritability of osteoporosis. This study aims to identify novel genetic loci associated with DXA-derived femoral neck (FNK) bone mineral density (BMD) and quantitative ultrasound of the heel calcaneus estimated BMD (eBMD), and to detect shared/causal variants for the two traits, to assess whether the …

The Significance Of Mfd And Oxidative Damage In Stationary-Phase Mutagenesis In Bacillus Subtilis, Holly Anne Martin

UNLV Theses, Dissertations, Professional Papers, and Capstones

The process of stationary-phase mutagenesis, also known as adaptative or stress-induced mutagenesis, is a phenomenon where bacterial cells accumulate mutations in non-replicative conditions. This process has mainly been studied in Escherichia coli and Bacillus subtilis; however, the underlying mechanisms found in each of these systems differ. Here, I use B.msubtilis to study previously understudied aspects of stationary-phase mutagenesis. In this dissertation, I describe work that has led to three major discoveries which are described below.

First in B. subtilis, Mfd is important for stationary-phase mutagenesis and its mutagenic function at regions of the genome that are transcriptionally upregulated has been …

The Bacillus Subtilis K-State Promotes Stationary-Phase Mutagenesis Via Oxidative Damage, Holly A. Martin, Amanda A. Kidman, Jillian Socea, Carmen Vallin, Mario Pedraza-Reyes, Eduardo A. Robleto

Life Sciences Faculty Research

Bacterial cells develop mutations in the absence of cellular division through a process known as stationary-phase or stress-induced mutagenesis. This phenomenon has been studied in a few bacterial models, including Escherichia coli and Bacillus subtilis; however, the underlying mechanisms between these systems differ. For instance, RecA is not required for stationary-phase mutagenesis in B. subtilis like it is in E. coli. In B. subtilis, RecA is essential to the process of genetic transformation in the subpopulation of cells that become naturally competent in conditions of stress. Interestingly, the transcriptional regulator ComK, which controls the development of competence, does influence the …