Genetics and Genomics Commons^™

Functions Of Dcp2 And Ski7 In Mrna Degradation, Minseon Kim, Ambro Van Hoof

Dissertations and Theses (Open Access)

Posttranscriptional gene regulation is essential to maintain gene expression fidelity. This is partially achieved by mRNA decay. When no longer required, mRNA is degraded by two alternative pathways. The decapping enzyme Dcp2 removes the 5` <sup>m7</sup>G cap of mRNAs, allowing Xrn1 to degrade the mRNA from the 5` end. Alternatively, mRNA is degraded from the 3` end by the RNA exosome.

While decapping by Dcp2 is a critical step in mRNA decay, its physiological function has been unclear. Null mutations of Saccharomyces cerevisiae DCP2 have been reported to be lethal in some studies but slow-growing in others. In this …

Investigating Barriers Experienced By Underrepresented Minorities In Becoming A Competitive Genetic Counseling Applicant, Katie Huang

Dissertations and Theses (Open Access)

Representation for both racial/ethnic and gender identity minorities in genetic counseling (GC) remains the lowest among similar healthcare professions. Barriers that underrepresented minority (URM) individuals face in becoming a competitive GC applicant have not yet been described. Academic capital (AC) is a theoretical framework describing the social processes necessary for individuals to navigate and succeed in higher education. This study aimed to characterize barriers experienced by applicants who self-identify as underrepresented and to explore how AC could identify areas for intervention. Prospective GC applicants for the 2021/2022 cycles were recruited to complete an anonymous online survey in Qualtrics through a …

Rare Variant Association Studies In Crohn’S Disease And Colorectal Cancer: Methods And Applications, Jiun-Sheng Chen

Dissertations and Theses (Open Access)

Genetic factors account for a substantial portion of Crohn’s disease and colorectal cancer (CRC) risk. Patients with Crohn’s disease, a condition that causes chronic inflammation of the gastrointestinal tract, are at increased risk of colorectal cancer morbidity and mortality. Genome-wide association studies using single marker approaches have identified loci responsible for these diseases, but disease susceptibility from rare variants is incompletely understood. This dissertation includes three chapters, two association studies for Crohn’s disease and CRC, and a statistical method to improve the power of statistical tests.

For Crohn’s disease, we performed targeted sequencing of 101 genes in 205 children with …

Spectrum And Incidence Of Primary And Therapy-Related Hematologic Malignancies In Individuals With Brca1 And Brca2 Pathogenic Variants, Rosemary Rogers, Rosemary Rogers

Dissertations and Theses (Open Access)

Therapy-related myeloid neoplasms (t-MN) are rare and deadly hematologic malignancies that develop following exposure to cytotoxic therapies such as radiation, chemotherapy, and poly (adenosine diphosphate-ribose)-ADP polymerase (PARP) inhibitors. Preliminary evidence suggests that germline BRCA1 and BRCA2 pathogenic and likely pathogenic (P/LP) variants may increase susceptibility to t-MNs due to the genes’ established role in DNA damage response. There is also evidence that individuals with BRCA1/2 P/LP variants may be more susceptible to developing primary hematologic malignancies. We reviewed medical records of 706 individuals with BRCA1/2 P/LP variants to assess hematologic malignancy diagnoses and t-MN development. Our study population was 5.1% …

Mixture Model Approaches To Integrative Analysis Of Multi-Omics Data And Spatially Correlated Genomic Data, Ziqiao Wang

Dissertations and Theses (Open Access)

Integrative genomic data analysis is a powerful tool to study the complex biological processes behind a disease. Statistical methods can model the interrelationships of the involved gene activities through jointly analyzing multiple types of genomic data from different platforms (vertical integration), or improve the power of a study through aggregating the same type of genomic data across studies (horizontal integration). In this dissertation, we propose statistical methods and strategies for integrative multi-omics data in association analysis of disease phenotypes, with an emphasis on cancer applications.

We develop a new strategy based on horizontal integration by leveraging publicly available datasets into …

Examining The Role Of The Drosophila Melanogaster Unc13 Protein In Open Field Activity Using Rnai, Islam Orabi

Honors Theses

Unc13 are proteins in the presynaptic neurons essential in controlling synaptic vesicle fusion and synaptic transmission. Recently, the reduction of Drosophila melanogaster Unc13 proteins (Dunc13), were found to result in a resistance to alcohol, highly reminiscent of tolerance formation. I investigated whether genetically reducing Dunc13 activity in Drosophila brain regions leads to different forms of behavioral plasticity using an open field activity paradigm. In my approach, a Dunc13 RNAi transgene was expressed in the Drosophila brain within the mushroom body, the ellipsoid body, and in all neurons. The activities of the flies were examined in the open field paradigm to …

The Biodiversity Of Deadwood-Associated Arthropods In The Southern Appalachian Mountains, Isabelle Ong

Honors Theses

A biodiversity hotspot is a location that has significantly elevated levels of biodiversity including many species found nowhere else, and which is also in danger of losing much of this diversity. By identifying biodiverse regions, conservation efforts can be targeted to those locations where they are likely to have the most beneficial impacts. We looked at deadwood associated arthropods within the Southern Appalachian Mountains to examine centers of biodiversity. Nine logs were sampled, three of which were located in Bankhead National Forest and six were located in the Great Smoky Mountains. Polymerase chain reaction was used to amplify the mitochondrial …

Validation Of Anti-Oxidative Stress Genes From Genome-Wide Screening Of Escherichia Coli, Carson Ercanbrack

Chemistry & Biochemistry Undergraduate Honors Theses

The primary purpose of this project is to evaluate the genes that play a role in the oxidative stress response in Escherichia coli. In doing so, the entire genome of E. coli was subject to throughput in which individual genes were determined to have a role in the bacteria’s oxidative stress response. Moreover, this project focused on the validation of the genes that were able to pass the initial throughput stage. The genes were subject to two forms of validation. In the first validation technique, candidate genes were overexpressed and minimum inhibitory concentrations of hypochlorous acid were taken. Following, a …

Lotus: A Web-Based Computational Tool For The Preliminary Investigation Of A Novel Mst Method Utilizing A Library Of 16s Rrna Bacteroides Otus, Ginger Dewitte

Master's Theses

Microbial Source Tracking (MST) is a field of study that attempts to identify the source of fecal contamination in waterways in order to assist with development of remediation strategies. Biologists at Cal Poly Center for Applications in Biotechnology (CAB) are developing a new MST method using microbes from the genus Bacteroides. Bacteroides species are host-specific microorganisms that can theoretically be used to trace back to a single host species. After fecal samples are collected, biologists use Next-Generation Sequencing (NGS) techniques to obtain only the genetic sequences of microorganisms belonging to the phylum Bacteroidetes. Investigators hypothesize that similar sequences belong …

Dynamics Of Hybrid Zones At A Continental Scale, Bradley T. Martin

Graduate Theses and Dissertations

Hybridization has traditionally been viewed as a happenstance that negatively impacts populations, but is now recognized as an important evolutionary mechanism that can substantially impact the evolutionary trajectories of gene pools, influence adaptive capacity, and contravene or reinforce divergence. Physiographic processes are important drivers of dispersal, alternately funneling populations into isolation, promoting divergence, or facilitating secondary contact of diverged populations, increasing the potential for hybridization. In North America, glacial-interglacial cycles and geomorphological changes have provided a dynamic backdrop over the last two million years that promoted such oscillations of population contraction and expansion. These biogeographic processes have resulted in regional …

Mapping And Characterization Of Mutagen Sensitivity Genes In Drosophila Malanogaster, Alexis Nystrom

Graduate Theses

The information contained within DNA is vital to directing all biological processes. All organisms have repair mechanisms in place to repair DNA damage quickly and efficiently. Without these repair pathways, DNA can acquire harmful mutations that can compromise the survival of an organism. Studies of DNA repair in Drosophila melanogaster have focused on mutagen sensitive (mus) mutants, each of which contain a mutation that renders them incapable of performing DNA repair. Since a majority of these mus genes are unmapped, the goal of this project was to determine what genes in the Drosophila melanogaster genome are mus106 and mus108. Presence …

Determination Of Human Shedding Propensity Based On Str Results, Genevieve Trapani

Student Theses

Trace DNA evidence may be discovered at a crime scene after having been deposited by a person of interest via active or passive transfer. Based on previous studies, passive transfer of one’s DNA is influenced by their shedding propensity, or probability of depositing a detectable amount of DNA through touch. Determining the shedding propensity of a person of interest can aid in trace DNA interpretation in forensic casework. This study explored STR profile quality and the presence of a DNA mixture for different skin surface locations, including fingertips before and after handwashing. As expected, unwashed fingers showed a higher prevalence …

The Diversity And Evolution Of Phenazine Biosynthesis Pathways In Enterobacterales, Christian Leise

Honors Theses

Enterobacterales is an order of Gram-negative bacteria that encompasses plant and animal pathogens and organisms of industrial importance. Some of these bacteria produce secondary metabolites classified as phenazines (Phz). Studies in other groups of microorganisms revealed that phenazines are redox-active and exhibit broad antibacterial, antifungal, and antiparasitic activity. Enterobacterales are known to produce phenazines, but details about the diversity, biochemistry, and function of phenazine metabolites in these organisms are missing. In this work, we screened the National Center for Biotechnology Information (NCBI) GenBank for genome sequences of phenazine-producing (Phz+) Enterobacterales. Additionally, genomes of Phz+ strains Pectobacterium carotovorum cc303 and …

Using Crispr-Cas9 To Characterize The Role Of Gli-Similar 3 (Glis3) In Insulin Regulation, Pancreatic Development, And Type 2 Diabetes, Lilyanne Grieve

Honors College Theses

The prevalence of type 2 diabetes continues to rise nationally and internationally, impacting millions of people worldwide. Type 2 diabetes results from insulin resistance leading to chronic hyperinsulinemia and dysfunction of the insulin producing β cells of the pancreas. While environmental factors can influence the development of type 2 diabetes, research has shown genetics are also involved. Gli-similar 3 (Glis3), a Krüppel-like zinc finger transcription factor, has been identified as a novel regulator of insulin transcription. Evidence has shown that loss-of-function Glis3 mutations decrease insulin expression, implicating Glis3 in the development of type 2 diabetes. However, the distinct role Glis3 …

Epigenome-Wide Association Study Of Kidney Function Identifies Trans-Ethnic And Ethnic-Specific Loci, Charles E. Breeze, Anna Batorsky, Mi Kyeong Lee, Mindy D. Szeto, Xiaoguang Xu, Daniel L. Mccartney, Rong Jiang, Amit Patki, Holly J. Kramer, James M. Eales, Laura Raffield, Leslie Lange, Ethan Lange, Peter Durda, Yongmei Liu, Russ P. Tracy, David Van Den Berg, Nhlbi Trans-Omics For Precision Medicine (Topmed) Consortium, Topmed Mesa Multi-Omics Working Group, Kathryn L. Evans, William E. Kraus, Donna K. Arnett

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: DNA methylation (DNAm) is associated with gene regulation and estimated glomerular filtration rate (eGFR), a measure of kidney function. Decreased eGFR is more common among US Hispanics and African Americans. The causes for this are poorly understood. We aimed to identify trans-ethnic and ethnic-specific differentially methylated positions (DMPs) associated with eGFR using an agnostic, genome-wide approach.

METHODS: The study included up to 5428 participants from multi-ethnic studies for discovery and 8109 participants for replication. We tested the associations between whole blood DNAm and eGFR using beta values from Illumina 450K or EPIC arrays. Ethnicity-stratified analyses were performed using linear …

Changes In Gene Sequence That Cause Discordances Involving Disease In Monozygotic Twins, Kacie Jacques

Thinking Matters Symposium

Identical twins or, monozygotic twins, occur when the egg in a mother is fertilized, but one zygote divides into two separate embryos. Monozygotic twins are considered to be genetically identical, but most twins often display discordances, some involving diseases or disorders. Some of these differences are due to environmental factors. For example, one twin may have diabetes due to diet. Recent literature has shown that some differences in monozygotic twins may be due to changes in gene sequence, as opposed to random, environmental or epigenetic factors. Identical twins from pedigrees with familial disease often show discordances. When looking at schizophrenia …

The Genetic Links Between Archaic And Modern Humans, Maria J. Orellana Rosales

Thinking Matters Symposium

Our modern physiology is the mixture of many archaic humans that once roamed our planet. The evidence of these archaic humans is still present in our DNA. This poster reviews how our understanding of ancient human genetics has drastically changed due to advances in molecular genetics. Neanderthal and Denisovan remains have been sequenced for nuclear and mitochondrial DNA. Neanderthal and Denisovan genetic ancestry have been identified by genomic studies in modern human populations across Eurasia and Pacific Island regions. Studies have shown a gene flow of 4±1% from Neanderthals to present-day Eurasians. Whereas, Papuan and Melanesian individuals share 4±0.7% more …

The Genes Of Pain, Alina Semenova

Thinking Matters Symposium

Pain is an important defense mechanism that protects us from environmental factors that might harm us. Our body's response to pain helps us to avoid injury. However, constant pain is a problem. Management of constant pain is an important area of research. Studies have shown that genetic variation contributes to pain sensitivity.

Numerous pain-related genes and their functional polymorphisms (CYP450, MOR-1, COMT, GCH1, etc.) have been identified in the past ten years. In particular, three opioid receptors (OPRM, OPRD and OPRK) are associated with pain sensitivity. One of the most studied human functional polymorphisms is the debrisoquine/sparteine polymorphism of CYP2D6 …

Genetically Modified Organisms Are Important But Also Controversial, Masen Pelletier

Thinking Matters Symposium

Genetically modified organisms (GMOs) are organisms containing a set or multiple sets of genes that have been introduced into the organism using laboratory techniques. In the instance of agriculture, the genes introduced provide advantages for the farmer and consumer by yielding plants that produce greater yields, longer growing seasons, longer shelf lives, greater concentrations of vitamins or add additional vitamins that are novel to the plant. There are two general ways that GM (genetically modified) crops are produced: the addition or removal of genes. This review focuses on an example of each strategy. An example of the latter is GM …

Understanding The Genetics Of Schizophrenia, Matthew Toohey

Thinking Matters Symposium

Schizophrenia has been considered heritable for a long time, but only with the advent of new technologies such as whole-genome sequencing and genome-wide association studies can we begin to identify specific molecular causes of schizophrenia. This poster will review some of the genetic variants that research groups have associated with schizophrenia. Current research has indicated that schizophrenia is a polygenic disease and has been linked to many genes. Some of these common risk variants are in protein coding sections of the DNA. These proteins are often linked to neurological development or immune system function. Other variants that have been associated …