Genetics and Genomics Commons^™

Genetic Effect On Body Mass Index And Cardiovascular Disease Across Generations, Chloé Sarnowski, Matthew P Conomos, Ramachandran S Vasan, James B Meigs, Josée Dupuis, Ching-Ti Liu, Aaron Leong

Faculty, Staff and Student Publications

BACKGROUND: Whether genetics contribute to the rising prevalence of obesity or its cardiovascular consequences in today's obesogenic environment remains unclear. We sought to determine whether the effects of a higher aggregate genetic burden of obesity risk on body mass index (BMI) or cardiovascular disease (CVD) differed by birth year.

METHODS: We split the FHS (Framingham Heart Study) into 4 equally sized birth cohorts (birth year before 1932, 1932 to 1946, 1947 to 1959, and after 1960). We modeled a genetic predisposition to obesity using an additive genetic risk score (GRS) of 941 BMI-associated variants and tested for GRS-birth year interaction …

Biallelic Variants In Ogdh Encoding Oxoglutarate Dehydrogenase Lead To A Neurodevelopmental Disorder Characterized By Global Developmental Delay, Movement Disorder, And Metabolic Abnormalities, Ella F Whittle, Madison Chilian, Ehsan Ghayoor Karimiani, Helga Progri, Daniela Buhas, Melis Kose, Rebecca D Ganetzky, Mehran Beiraghi Toosi, Paria Najarzadeh Torbati, Reza Shervin Badv, Ivan Shelihan, Hui Yang, Houda Zghal Elloumi, Sukyeong Lee, Yalda Jamshidi, Alan M Pittman, Henry Houlden, Erika Ignatius, Shamima Rahman, Reza Maroofian, Wan Hee Yoon, Christopher J Carroll

Faculty, Staff and Students Publications

PURPOSE: This study aimed to establish the genetic cause of a novel autosomal recessive neurodevelopmental disorder characterized by global developmental delay, movement disorder, and metabolic abnormalities.

METHODS: We performed a detailed clinical characterization of 4 unrelated individuals from consanguineous families with a neurodevelopmental disorder. We used exome sequencing or targeted-exome sequencing, cosegregation, in silico protein modeling, and functional analyses of variants in HEK293 cells and Drosophila melanogaster, as well as in proband-derived fibroblast cells.

RESULTS: In the 4 individuals, we identified 3 novel homozygous variants in oxoglutarate dehydrogenase (OGDH) (NM_002541.3), which encodes a subunit of the tricarboxylic acid cycle enzyme …

A Comparison Of Microsatellites And Single Nucleotide Polymorphisms For The Assessment Of Population Structure In The Amblyomma Maculatum Koch, 1844 Species Complex, Henrey A. Deese

Electronic Theses and Dissertations

The Gulf Coast tick, Amblyomma maculatum Koch, 1844 is widespread throughout North and Central America and is the primary vector for the emerging pathogen Rickettsia parkeri. In the U.S., the population in the Southwest (A. maculatum morphotype III) is morphologically different from the population east of the Rocky Mountains (A. maculatum morphotype II). This research tests the hypothesis that A. maculatum morphotype II and morphotype III represent distinct species through the analysis and comparison of 6 microsatellite loci and suite of 135,221 Single nucleotide polymorphisms (SNPs) generated from ddRADseq. Population genetic analysis of both microsatellites and SNPs …

Molecular Regulation Of The Salicylic Acid Hormone Pathway In Plants Under Changing Environmental Conditions, Christina A. M. Rossi, Eric J. R. Marchetta, Jong Hum Kim, Christian Castroverde

Biology Faculty Publications

Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience. We especially highlight advances in the thermosensitive mechanisms underpinning SA-mediated immunity, including differential regulation of key transcription factors (e.g., CAMTAs, CBP60g, SARD1, bHLH059), selective protein–protein interactions of the SA receptor NPR1, and dynamic phase separation of the recently identified …

The Evolutionary Causes And Consequences Of Mammalian Hybridization, Kelsie E. Hunnicutt

Electronic Theses and Dissertations

The natural recombination of divergent genomes within hybrid offspring provides windows through which we can study evolutionary processes and the dynamics of speciation. In this work, I use a combination of comparative and population genomics on both laboratory crosses of divergent rodent lineages and a hybrid zone of cottontail rabbits in the wild to study the causes and consequences of hybridization in mammals. Hybrid sterility is a common reproductive barrier between species that tends to preferentially manifest in the heterogametic sex and frequently genetically maps to the sex chromosomes. Thus, the sex chromosomes appear to play a special role in …

Analysis Of A Cathepsin Protease In Normal Development And Tumor Metastasis In Drosophila Melanogaster, Lindsey Fannin

Mahurin Honors College Capstone Experience/Thesis Projects

Cysteine cathepsins are an important class of fifteen proteases with involvement in normal development and tumor progression. To better understand their contribution to these processes, the cathepsin L protease in Drosophila melanogaster was studied. In part one of this project, the role of this cathepsin in the normal development of Drosophila wings was analyzed. The GAL4/UAS-system and RNAi were used to downregulate this cathepsin in various regions of the wing and progeny were inspected for phenotypic irregularities. An abnormal phenotype of curved wings was found and hypothesized to be a result of apoptosis. Further experimentation will be required to prove …

Intraspecific Hybrid Identification Of Black Walnuts Via Marker Assisted Selection, Makenna B. Thompson

Graduate Theses/Dissertations

The improvement of Eastern black walnut (Juglans nigra L.) cultivars could increase market expansion. Improved cultivars with superior qualities would increase profitability for both the seller and the buyer. Agronomically and economically important traits such as heavier nut weight, disease resistance, tree structure integrity, and yearly nut production can be efficiently improved by breeding black walnuts via marker-assisted selection. Microsatellite/simple sequence repeat markers were used in this research to determine potential intraspecific hybrids between ‘Football’ and ‘Sparrow’ cultivars. Intraspecific is defined as of the same genus and species. This quality makes it more difficult to identify hybrids because the parent …

Molecular Investigation Of Minor Genomic Populations And Biological Exposures In Human Health, Brandon Ned Johnson

Dissertations and Theses

The study of genetics has contributed to countless discoveries related to human health and disease. However, the complexities of human biology reside not only in the genome but also in the contributions from environmental exposures, as measured via the classical twin design. To understand the influence of biological exposures, I implemented study designs to explore both the health associations and propagation of foreign genetic material. Microchimerism has been studied for association with several clinical conditions, and I further investigated if male microchimerism could elucidate the etiology of Mayer-Rokitansky-Küster-Hauser syndrome. Prevalence of male microchimerism in women with no history of pregnancy …

Testing Evolutionary Conservation Of Sex Determination In Lepidoptera Using Crispr/Cas9 Gene Editing, Sophia Schroeder

Honors Theses

The mechanism of sex determination in Lepidoptera is largely unexplored, and limited to knowledge of only a few genes. Adult Lepidoptera have obvious sexually dimorphic qualities, such as their genitalia. However, significant sex determination genes are not imperative for the adult developmental stage. Knockouts of some sex determination genes (doublesex isoforms) are shown to be lethal in the embryonic and larval stages of development in several animals. However, it is unclear whether this is due to their respective impact on sex determination and sexual dimorphism, or the existence of another function, such as pleiotropy, within a particular gene. Moreover, …

Association Of Interpersonal Trauma And Polygenic Risk Scores With Depressive Symptoms In College Students, Rowan K. O'Hara

Theses and Dissertations

Major depression is considered a complex trait influenced by both polygenic risk factors and environmental exposures, such as childhood trauma. This study applied statistical genetic methods to calculate aggregate genetic risk for major depression to predict depressive symptoms scores in a college student sample. Data were from the Spit for Science (S4S) study in which college students from a large urban university self-reported interpersonal trauma (IPT) exposure prior to college and depressive symptoms from the past month (N = 7502; ancestry group: 20% African [AFR], 12% Admixed Americas [AMR], 10% East Asian [EAS], 49% European [EUR], 8% South Asian [SAS]). …

Revolutionary Advances In The Treatment Of Genetic Disease, Emma Kaitlyn Carrigan

Honors Theses and Capstones

No abstract provided.

Investigation Of The Function Of Protein Acyl Transferases Using Crispr-Cas9 To Create Null Mutants, Claire E. Christopher

Honors Theses and Capstones

24 Protein Acyl Transferases (PATs) have been identified in the model organism Arabidopsis thaliana. Despite knowing the enzymatic function of these genes (palmitoylation), the specific subcellular pathways, protein targets, and cellular activities of these proteins remain unknown. To investigate the pathways that PAT genes are involved in, deletion mutations were created in several genes and the phenotype of the organisms carrying homozygous mutations was observed. To introduce mutations, the CRISPR/Cas9 system was inserted into the plant’s genome using Agrobacterium tumefaciens to cause deletions in PAT genes of interest. To date, no CRISPR-induced pat mutants have a noticeable phenotype. These …

Investigating The Role Of Bromodomain Proteins On Histone Post-Translational Modifications In Toxoplasma Gondii, Joshua Steven Berthiaume

Honors Theses and Capstones

Toxoplasma gondii is a prevalent pathogenic parasite that infects approximately 25 percent of the US population. For the parasite to successfully establish and maintain infection in its host, properly controlled regulation of gene expression is critical. One way Toxoplasma regulates gene expression is through modification of histone proteins that bind to DNA and can control gene accessibility. Acetylation is a modification that is added to histones that changes chromatin structure to enhance gene activation. Histone acetylation can also regulate gene expression by recruitment of important regulators such as bromodomain proteins (BDP). A previous study showed that loss of the bromodomain …

The Effect Of Genetic Relatedness On Mate Selection And Spatial Distribution In The American Alligator, Alligator Mississippiensis, Mark Hoog

College of Graduate Studies: Theses & Dissertations

To date, most genetic studies on the American alligator (Alligator mississippiensis) have focused on population genetics and multiple paternity. There have not been any studies looking at how relatedness affects alligator behavior and movement. This study focused on three main questions: 1) what is the genetic diversity among alligators in this location? 2) can parentage be accurately defined among parents and offspring? and 3) how does individual relatedness affect their spatial distribution? We examined the relatedness of 174 unique individuals from the Okefenokee Swamp Park, in South Georgia, USA. In addition, we placed Telonics^® satellite tags on …

Methylation Patterns Across Tissue Type And Time In Peromyscus Leucopus: A Targeted Museum Study, Loryn Smith

Master's Theses or Doctor of Nursing Practice

Museum specimens are a vital data source for many types of studies. One relatively new use includes studying methylation patterns. Methylation patterns are a form of epigenetics or how gene expression changes without alteration of the genetic code. These patterns have been examined in many mammals. However, the focus has previously been on overall epigenetic patterns. Few studies have investigated whether methylation patterns differ across tissue types, time, or preservation method. In this study, I compared methylation patterns in muscle, liver, toe pads, and nasal bones from Peromyscus leucopus (white-footed mouse) museum specimens collected in 2022, 2018, 2014, and 2008 …

Biodiversity Of Philippine Marine Fishes: A Dna Barcode Reference Library Based On Voucher Specimens, Katherine E. Bemis, Matthew G. Girard, Mudjekeewis D. Santos, Kent E. Carpenter, Jonathan R. Deeds, Diane E. Pitassy, Nicko Amor L. Flores, Elizabeth S. Hunter, Amy C. Driskell, Kenneth S. Macdonald Iii, Lee A. Weigt, Jeffrey T. Williams

Biological Sciences Faculty Publications

Accurate identification of fishes is essential for understanding their biology and to ensure food safety for consumers. DNA barcoding is an important tool because it can verify identifications of both whole and processed fishes that have had key morphological characters removed (e.g., filets, fish meal); however, DNA reference libraries are incomplete, and public repositories for sequence data contain incorrectly identified sequences. During a nine-year sampling program in the Philippines, a global biodiversity hotspot for marine fishes, we developed a verified reference library of cytochrome c oxidase subunit I (COI) sequences for 2,525 specimens representing 984 species. Specimens were primarily purchased …

Adjusting For Gene-Specific Covariates To Improve Rna-Seq Analysis, Hyeongseon Jeon, Kyu-Sang Lim, Yet Nguyen, Dan Nettleton

Mathematics & Statistics Faculty Publications

Summary

This paper suggests a novel positive false discovery rate (pFDR) controlling method for testing gene-specific hypotheses using a gene-specific covariate variable, such as gene length. We suppose the null probability depends on the covariate variable. In this context, we propose a rejection rule that accounts for heterogeneity among tests by employing two distinct types of null probabilities. We establish a pFDR estimator for a given rejection rule by following Storey's q-value framework. A condition on a type 1 error posterior probability is provided that equivalently characterizes our rejection rule. We also present a suitable procedure for selecting a tuning …

Genetic And Pharmacogenetics Associations Of Cancer Disparities In Appalachia, Nan Lin

Theses and Dissertations--Pharmacy

Individuals residing in Appalachian regions have significant health disparities, including higher cancer incidence and mortality rates. Previous studies have addressed the impact of socioeconomic status and environmental risk factors on Appalachia cancer disparities, while few studies have evaluated genetic risk factors.

Germline whole exome sequencing samples from 7,078 individuals with cancer (759 Appalachians) were evaluated. Demographics and relatedness were assessed using KING. Ethnicity was verified by principal component analysis using TRACE, which included 6,034 individuals (85%) of European genetic ancestry. After QC filtering, 5,980 individuals were analyzed. To assess the overall predisposition of hereditary disease, gene level frequency of likely …

Use Of Molecular Genetics To Investigate Population Structure And Swayback In Horses, Navid Yousefimashouf

Theses and Dissertations--Veterinary Science

The present research incorporated molecular genetic methods to 1) investigate the genetic basis of Juvenile Onset Lordosis or Swayback in the American Saddlebred horses; and 2) conduct a population genetic study to compare the Persian Kurdish, Persian Arabian and American Thoroughbred horse populations.

Juvenile-onset lordosis, or swayback, is a condition in horses where the conformational topline back curvature drops significantly within the first two years of life. The trait has a higher prevalence in Saddlebreds (5%). Prior research on them quantified the trait using a Measurement of Back Contour (MBC), defining an MBC of >7.0 centimeters as swayback, and8.0) MBC …

Biomarker Identification For Breast Cancer Types Using Feature Selection And Explainable Ai Methods, David E. La Rosa Giraud

Honors Undergraduate Theses

This paper investigates the impact the LASSO, mRMR, SHAP, and Reinforcement Feature Selection techniques on random forest models for the breast cancer subtypes markers ER, HER2, PR, and TN as well as identifying a small subset of biomarkers that could potentially cause the disease and explain them using explainable AI techniques. This is important because in areas such as healthcare understanding why the model makes a specific decision is important it is a diagnostic of an individual which requires reliable AI. Another contribution is using feature selection methods to identify a small subset of biomarkers capable of predicting if a …

Statistical Methods For Gwas And The Impact Of Diabetic Medication Adherence On Healthcare Costs, Meida Wang

Dissertations, Master's Theses and Master's Reports

This dissertation includes three Chapters. In Chapter One, we develop a computationally efficient clustering linear combination approach to jointly analyze multiple phenotypes for GWAS. In this paper, based on the existing CLC method and ACAT strategy, we develop the ceCLC method to test association between multiple phenotypes and a genetic variant. In Chapter Two, we develop a novel method called sCLC for association studies of multiple phenotypes and a genetic variant based on GWAS summary statistics. Simulation results show that sCLC can control Type I error rates well and has the highest power in most scenarios. In Chapter Three, we …

Sequencing Antisense Transcriptome Of Populus Through Antisense/Sense Transcript Pair Enrichment, Emma V. Burke

Dissertations, Master's Theses and Master's Reports

Past transcriptome research on plants focused primarily on protein coding genes, and only recently researchers began looking into the non-protein coding regions that may play significant roles in gene regulation. Antisense RNA transcripts that are found naturally in the cell share complementary sequence with sense transcripts and have been shown to regulate expression of their sense counterparts. Since antisense RNA has been largely under-studied and difficult to sequence because of their low relative abundance, new methods are needed to target antisense RNA for efficient genome-wide profiling. To address this gap in methods to efficiently and cost effectively enrich antisense RNA …

Statistical Methods For Gene Selection And Genetic Association Studies, Xuewei Cao

Dissertations, Master's Theses and Master's Reports

This dissertation includes five Chapters. A brief description of each chapter is organized as follows.

In Chapter One, we propose a signed bipartite genotype and phenotype network (GPN) by linking phenotypes and genotypes based on the statistical associations. It provides a new insight to investigate the genetic architecture among multiple correlated phenotypes and explore where phenotypes might be related at a higher level of cellular and organismal organization. We show that multiple phenotypes association studies by considering the proposed network are improved by incorporating the genetic information into the phenotype clustering.

In Chapter Two, we first illustrate the proposed GPN …

Alzheimer’S Disease Genetics And Short-Chain Fatty Acid Treatment In Studies Of The Murine Gut Microbiome, Diana Zajac

Theses and Dissertations--Physiology

Elucidating the relationship of the gut microbiome in Alzheimer's Disease (AD) risk and pathogenesis is an area of intense interest. Since 60 to 80% of AD risk is related to genetics and APOE alleles represent the most impactful genetic risk factors for AD, their mechanism(s) of action are under intense scrutiny.

First, I conducted a study on APOE targeted replacement mice to investigate the impact of APOE alleles on the murine gut microbiome. The relative abundance of bacteria from the family Ruminococacceae and related genera increased with APOE2 status. The relative abundance of the class Erysipelotrichia increased with APOE4 status, …

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

College of Graduate Studies: Theses & Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …

Generation Of Chimeric Rhinoviruses Presenting Sars-Cov-2 Broadly Neutralizing Epitopes And Their Antigenicity Characterization, Danish Ansari

Biotechnology Theses

The global COVID pandemic is not yet fully under control as there were over 21 million new cases of SARS-CoV-2 infections and over 50,000 deaths globally as of January of 2022. A heavily mutated variant of concern, Omicron is responsible for most of these cases which demands an urgency for a new vaccine. NIH reports over 180 vaccine candidates that use various strategies currently in development. However, a recurring concern with these vaccines is that the continuous viral mutations decrease the efficacy of vaccines. Therefore, we proposed to construct a human rhinovirus (HRV) based chimeric virus containing highly conserved, broadly …

Unusual Chromosome Configurations: Evaluation Of Sex Univalent And Trivalent Chromosome Models, Ashley B. Borseth

Master’s Theses

Aneuploidy, or abnormal number of chromosomes in a haploid set, in XY/XX organisms has consequences that can impede physical and cognitive development. To prevent aneuploidy, cellular division relies on the correct position of paired chromosomes and subsequent segregation in the meiotic program. If connections between paired chromosomes sever or errors in chromosome contraction towards spindle poles arise, aneuploidy occurs. Many arthropod species have chromosomes that naturally do not pair, or that pair differently than typical autosomes. Through the evaluation of such systems, novel insights into chromosomal coordination and positioning may be revealed. The objective of this study is twofold: (1) …

Knockout Of Endospanin 1 Via Crispr In Zebrafish, Danio Rerio, Jared Kittinger

Williams Honors College, Honors Research Projects

I made endospanin 1 knockout (KO) zebrafish to examine its effects on lipid and bone metabolism. Endospanin 1, or leptin receptor overlapping transcript (leprot), is a cytosolic protein linked to the protein hormone leptin that influences the trafficking of leptin receptors to the plasma membrane of cells. Genes for endospanin and tyrosinase (a pigmentation enzyme) were targeted via a microinjection of guide RNAs and CRISPR Cas9 into zebrafish embryos at 2-4 cell stages. I was able to disrupt the endospanin 1 gene (based upon the disruption of tyrosinase), but very few mutant zebrafish fully developed into adults. Only low KO …

Advancing Methods Of Diet Analysis: A Case Study Using Degraded Merlin (Falco Columbarius) Prey Remains, Taylor A. Coon

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Prey remains have long been used as a mechanism to approach diet analyses. As understanding diet is key to comprehending ecosystem dynamics, prey remains identification requires a unique methodological approach to determine diversity within a sample. With the advancement of technology, molecular protocols designed for species-specific identification have improved to incredible accuracy and precision. Yet, the visual identification method has remained a predominant technique within diet studies. With entry-level observers, we matched visual identifications with molecular-based methods to quantify the accuracy of the visual identification method. This study determined what fraction of visually identified prey remains could be correctly identified …

Placing The Evolutionary History Of Desmognathus Salamanders In Context: A Phylogeographic Approach, Kara Jones

Theses and Dissertations--Biology

Patterns of genetic variation do not arise in a vacuum but are instead shaped by the interplay between evolutionary forces and ecological constraints. Here, I use a phylogeographic approach to examine the role that ecology played in lineage divergence in the Desmognathus quadramaculatus species complex (Family: Plethodontidae), which consists of three nominal species: D. quadramaculatus, D. marmoratus, and D. folkertsi. Previous phylogenetic studies have shown that individuals from these species do not form clades based on phenotype. My approach to reconciling phylogenetic discordance was two-fold, using (1) genome-wide markers to provide insight into the …