Genetics and Genomics Commons^™

A De Novo Missense Variant In Ezh1 Associated With Developmental Delay Exhibits Functional Deficits In Drosophila Melanogaster, Sharayu V Jangam, Lauren C Briere, Kristy L Jay, Jonathan C Andrews, Melissa A Walker, Lance H Rodan, Frances A High, Undiagnosed Diseases Network, Shinya Yamamoto, David A Sweetser, Michael F Wangler

Faculty, Staff and Students Publications

EZH1, a polycomb repressive complex-2 component, is involved in a myriad of cellular processes. EZH1 represses transcription of downstream target genes through histone 3 lysine27 (H3K27) trimethylation (H3K27me3). Genetic variants in histone modifiers have been associated with developmental disorders, while EZH1 has not yet been linked to any human disease. However, the paralog EZH2 is associated with Weaver syndrome. Here we report a previously undiagnosed individual with a novel neurodevelopmental phenotype identified to have a de novo missense variant in EZH1 through exome sequencing. The individual presented in infancy with neurodevelopmental delay and hypotonia and was later noted to have …

Genetic Control Of Mrna Splicing As A Potential Mechanism For Incomplete Penetrance Of Rare Coding Variants, Jonah Einson, Dafni Glinos, Eric Boerwinkle, Peter Castaldi, Dawood Darbar, Mariza De Andrade, Patrick Ellinor, Myriam Fornage, Stacey Gabriel, Soren Germer, Richard Gibbs, Craig P Hersh, Jill Johnsen, Robert Kaplan, Barbara A Konkle, Charles Kooperberg, Rami Nassir, Ruth J F Loos, Deborah A Meyers, Braxton D Mitchell, Bruce Psaty, Ramachandran S Vasan, Stephen S Rich, Michael Rienstra, Jerome I Rotter, Aabida Saferali, Moore Benjamin Shoemaker, Edwin Silverman, Albert Vernon Smith, Nhlbi Trans-Omics For Precision Medicine (Topmed) Consortium; Pejman Mohammadi, Pejman Mohammadi, Stephane E Castel, Ivan Iossifov, Tuuli Lappalainen

Faculty, Staff and Student Publications

Exonic variants present some of the strongest links between genotype and phenotype. However, these variants can have significant inter-individual pathogenicity differences, known as variable penetrance. In this study, we propose a model where genetically controlled mRNA splicing modulates the pathogenicity of exonic variants. By first cataloging exonic inclusion from RNA-sequencing data in GTEx V8, we find that pathogenic alleles are depleted on highly included exons. Using a large-scale phased whole genome sequencing data from the TOPMed consortium, we observe that this effect may be driven by common splice-regulatory genetic variants, and that natural selection acts on haplotype configurations that reduce …

Gene Expression Effects On Productivity And Stress Tolerance In Polyclonal Plantings Of Populus Deltoides, Macy Gosselaar

Theses and Dissertations

Polyclonal plantings of Populus deltoides are expected to display increased site resource use, productivity, and tolerance to stress through plasticity changes leading to niche differentiation (i.e changes to crown/canopy structures). In the present study, P. deltoides Clones S7C8, 110412, and polyclonal plots were tested for differentially expressed genes and enriched biological pathways between planting schemes. Transcriptomic analysis of leaves revealed upregulation of an active growth gene and gene family members that play important roles in plant stress and stress tolerance in polyclonal plantings. A gene associated with oxidative stress was upregulated in polyclonal plantings across all treatments. Secondary metabolic pathways …

Upland Cotton And Nematodes: An Analysis Of Historical Resistance, Upcoming Threats, And Co-Inoculation Effects, Amanda Gaudin

Theses and Dissertations

Upland cotton (Gossypium hirsutum ) is an important fiber crop grown throughout the southern United States. Plant-pathogenic nematodes are worm-like animals that feed on the roots of most agronomic crops, including cotton. The southern root-knot nematode (Meloidogyne incognita, RKN) and the reniform nematode (Rotylenchulus reniformis, RN) cause significant yield losses in cotton every year. Current sources of resistance are effective but limited, therefore historical screenings of cotton accessions were revisited in search for novel resistance sources. None were identified but many of the screened accessions possessed markers of known root-knot nematode and reniform nematode resistance. …

Spatial Structure Formation By The Post-Transcriptional Gene Regulator Rsme In Pseudomonas Fluorescens Pf0-1, Anton Evans

Electronic Theses and Dissertations

Microorganisms are often found in microbial communities we call biofilms. Organisms living in these crowded environments have significant evolutionary pressure to retain access to the resources necessary to sustain life. My research uses the bacterium Pseudomonas fluorescens Pf0-1 to study how organisms evolve strategies to solve this crowding problem as aging colonies repeatedly generate mutant patches. These mutants expand the reach of the colony resulting in decreased local density as they push themselves up to the resource rich surface. These spatial structures result from social interactions between the mutant and the parental cells mediated through extracellular secretions, resulting in the …

Genotype Error Due To Low-Coverage Sequencing Induces Uncertainty In Polygenic Scoring, Ella Petter, Yi Ding, Kangcheng Hou, Arjun Bhattacharya, Alexander Gusev, Noah Zaitlen, Bogdan Pasaniuc

Faculty, Staff and Student Publications

Polygenic scores (PGSs) have emerged as a standard approach to predict phenotypes from genotype data in a wide array of applications from socio-genomics to personalized medicine. Traditional PGSs assume genotype data to be error-free, ignoring possible errors and uncertainties introduced from genotyping, sequencing, and/or imputation. In this work, we investigate the effects of genotyping error due to low coverage sequencing on PGS estimation. We leverage SNP array and low-coverage whole-genome sequencing data (lcWGS, median coverage 0.04×) of 802 individuals from the Dana-Farber PROFILE cohort to show that PGS error correlates with sequencing depth (p = 1.2 × 10

Beyond The Exome: What’S Next In Diagnostic Testing For Mendelian Conditions, Monica H Wojcik, Chloe M Reuter, Shruti Marwaha, Medhat Mahmoud, Michael H Duyzend, Hayk Barseghyan, Bo Yuan, Philip M Boone, Emily E Groopman, Emmanuèle C Délot, Deepti Jain, Alba Sanchis-Juan, Genomics Research To Elucidate The Genetics Of Rare Diseases (Gregor) Consortium, Lea M Starita, Michael Talkowski, Stephen B Montgomery, Michael J Bamshad, Jessica X Chong, Matthew T Wheeler, Seth I Berger, Anne O'Donnell-Luria, Fritz J Sedlazeck, Danny E Miller

Faculty, Staff and Student Publications

Despite advances in clinical genetic testing, including the introduction of exome sequencing (ES), more than 50% of individuals with a suspected Mendelian condition lack a precise molecular diagnosis. Clinical evaluation is increasingly undertaken by specialists outside of clinical genetics, often occurring in a tiered fashion and typically ending after ES. The current diagnostic rate reflects multiple factors, including technical limitations, incomplete understanding of variant pathogenicity, missing genotype-phenotype associations, complex gene-environment interactions, and reporting differences between clinical labs. Maintaining a clear understanding of the rapidly evolving landscape of diagnostic tests beyond ES, and their limitations, presents a challenge for non-genetics professionals. …

Sensing The Rhizosphere: Microbial Transcriptome Responses To Root Exudates And Redox-Active Metabolites, Ankita Bhattacharyya

Dissertations

The term “rhizosphere” describes the dynamic interface between plant roots and soil influenced by root exudates. It is a hotspot of microbial activity, plant-microbe, and microbe-microbe interactions. Distinct variations in bacterial diversity are thought to be driven by plant root exudates. However, the molecular details of these processes still remain unclear.

I addressed this gap by focusing on two strains, Pseudomonas synxantha 2-79 and Burkholderia lata 383, representing diverse groups of Gammaproteobacteria comprised of species with environmental, agricultural, and medical significance. In the first part of this project, we used a combination of metabolomics and RNA-seq to characterize transcriptome responses …

The Impact Of Soil Disturbance On Soil Bacterial Community Composition, Marie A. Rodriguez, Mark Peach, Timothy D. Trott

Research in Biology

Soil bacterial communities are an important part of terrestrial ecosystems due to their roles in biogeochemical cycling processes. Consequently, understanding how soil disturbance affects the soil bacterial diversity is vital to understanding the entire ecosystem. In this study we examined the effects of soil disturbance (by mining) on the soil bacterial community composition from three sites on Bauxite Ridge in Southeast Tennessee compared to three undisturbed sites in a nearby location. The soil bacterial community was analyzed by 16S rDNA amplicon sequencing of total DNA extracted from the soil samples collected from each of the six sites. Characterization of the …

Examining The Different Soil Horizons Of White Oak Mountain, Tn And Their Effect On The Soil Microbial Community, Ji Won Moon, Timothy D. Trott

Research in Biology

Soil microorganisms participate in the diverse interaction within virtually all ecosystems, consequently affecting the associated human and animal population. Identifying how edaphic variables alter the functional and taxonomic diversity of the soil microbial community requires an examination of total microbial soil diversity and abundance. This research study examined the effect of soil depth and horizon on the soil microbial community composition of White Oak Mountain. The soil microbial community was characterized by 16S/18S/ITS rDNA amplicon sequencing of the DNA extract of six samples from the three major soil types identified: HcE, MoE, and uMvC. OTU clustering analysis and both alpha …

A Phylogenetic Analysis Of The Leuctra Ferruginea (Walker 1852) Species Group (Plecoptera: Leuctridae), Madison Layer

Masters Theses & Specialist Projects

Leuctra Stephens, 1836 is a genus of Plecoptera (Leuctridae) distributed widely across the Northern Hemisphere, with approximately 210 species reported from eastern North America, Europe, northern Africa, and sporadically across Asia. Eastern North America harbors a small proportion of the global Leuctra fauna (ca. 15% = 31 species), most of which occur in the ancient Appalachian Mountains and unglaciated landscapes in the southeastern USA. Nearctic Leuctra species, except for L. moha and L. crossi, have been divided into five species groups based on external male morphological characteristics. Current phylogenies of Nearctic Leuctra are partial and preliminary, and no comprehensive …

Assessing The Effect Of Reservoirs On Gene Flow In The Southern Two-Lined Salamander (Eurycea Cirrigera), Anna Favalon

Masters Theses & Specialist Projects

Biodiversity is an essential component of natural environmental dynamics. Unfortunately, diversity is threatened by human activities and relies on conservation efforts. An important aspect of biodiversity conservation lies in protecting population connectivity and gene flow. In the mid-1900s, many Kentucky rivers were dammed, creating deep, lentic reservoirs in the valleys once occupied by dynamic, lotic rivers. For species inhabiting the rivers and associated tributaries, the central reservoirs may reduce connectivity among populations and impose a barrier to gene flow. The connectivity of populations on landscapes altered by the creation of reservoirs can be assessed by merging the principles of landscape …

A Systems Genetics Approach To Drosophila Melanogaster Models Of Rare And Common Neurodevelopmental Disorders, Rebecca Macpherson

All Dissertations

Fetal Alcohol Spectrum Disorders are a group of disorders resulting from prenatal alcohol exposure, presenting with neurodevelopmental and facial abnormalities of varying severity. SSRIDDs and CdLS are rare disorders of chromatin modification, resulting in patients with a wide range of craniofacial, digit and/or neurodevelopmental abnormalities. All of these disorders have a wide range of clinical phenotypes and disease severity, yet the role of potential genetic modifiers and gene-gene or gene-environment interactions in disease pathogenesis is largely unknown and cannot be studied in humans. Insufficient numbers of patients with a single rare disorder prevent investigation of genetic factors beyond the focal …

Perspectives On The Application Of Pharmacogenomics In Patient Care, Erika Meaddough

All Dissertations

Pharmacogenomics, the study of the genetic contribution to inter-individual differences in drug response, has great potential for realizing the goals of precision medicine: the right drug, for the right patient, at the right time. However, application in the clinical setting, through the use of pharmacogenetic testing, still has not gained widespread acceptance. This work describes multiple aspects of pharmacogenomics, which drive current research in this field.

Chapter I is an introduction to pharmacogenomics. Regulatory agencies and professional organizations across the globe provide information about gene-drug interactions that could lead to adverse drug reactions, and/or therapeutic failure. Risks for poor health …

Elucidating Mechanisms Of Rad51 Regulation During The Replication Stress Response, Alexandra Hawks

All Dissertations

The genome must be accurately and efficiently replicated each cell cycle to ensure there is not accumulation of mutations or structural rearrangements. When an active replication fork stalls, there are multiple DNA damage tolerance (DTT) pathways that can act to both protect integrity of DNA at the fork and restart replication. RAD51, a vital recombinase, works with HLTF, ZRANB3, and SMARCAL1 or FBH1 to regress stalled replication forks. RAD51 is loaded and stabilized onto the replication fork to protect the newly synthesized DNA from degradation. RAD51 is also active during the template switching DDT pathway. This pathway can be utilized …

Investigation Of Orthohantavirus Genetics In Rodent Reservoirs And Clinical Samples, Samuel Melvin Goodfellow

Biomedical Sciences ETDs

Orthohantaviruses are negative-sense, single stranded RNA viruses with trisegmented genomes that can cause severe disease in humans and are carried by several host reservoirs throughout the world. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of hantavirus cardiopulmonary syndrome (HCPS) with a fatality rate of ~36% and the highest cases occuring in the southwest region. The primary SNV host reservoir is thought to be the western deer mouse, Peromyscus maniculatus, however it has been shown that other rodents can carry different orthohantaviruses. We designed a pan-orthohantavirus detection tool to survey several small mammal populations throughout New …

Anything But Bland: Uncovering The Hidden Diversity And Genomic Origin Of The Threatened Vanilla Spice, Paige Ellestad

Boise State University Theses and Dissertations

Conserving the genetic diversity of crop species and their wild relatives has become a mounting concern as the detrimental effects of climate change, habitat destruction, and genetic erosion are being realized. In this epoch of unprecedented biodiversity loss, the genetic resources needed to improve crops may be at risk of extinction. Even one of the most iconic spices, vanilla, is threatened. Wild populations of the main vanilla producing species, Vanilla planifolia Andrews (Orchidaceae), are being rapidly extirpated due to deforestation and illegal harvesting in their native range. On top of that, clonal propagation methods within cultivated plants are hypothesized to …

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 …

An Overview Of Risk Factors For Neural Tube Defects And An Investigation Within South Carolina, Lucy Pulliam

All Dissertations

Neural tube defects (NTDs) are congenital anomalies that affect both the morbidity and mortality of infants worldwide. Inadequate levels of the vitamin folate in women during early pregnancy have been shown to be a risk factor for NTDs. Recent efforts to ensure adequate folate intake in mothers have been helpful in reducing but not eliminating NTDs. This dissertation examines additional risk factors for NTDs as possible focus areas for decreasing NTD occurrence.

Chapter Two and Chapter Three are literature reviews conducted to explore select factors associated with an increased risk of NTDs and how these factors may affect folate availability …