Genetics and Genomics Commons^™

A Longitudinal Cline Characterizes The Genetic Structure Of Human Populations In The Tibetan Plateau, Choongwon Jeong, Benjamin M. Peter, Buddha Basnyat, Maniraj Neupane, Geoff Childs, Sienna Craig, John Novembre, Anna Di Rienzo

Dartmouth Scholarship

Indigenous populations of the Tibetan plateau have attracted much attention for their good performance at extreme high altitude. Most genetic studies of Tibetan adaptations have used genetic variation data at the genome scale, while genetic inferences about their de- mography and population structure are largely based on uniparental markers. To provide genome-wide information on population structure, we analyzed new and published data of 338 individuals from indigenous populations across the plateau in conjunction with world- wide genetic variation data. We found a clear signal of genetic stratification across the east- west axis within Tibetan samples. Samples from more eastern locations …

Post-Transcriptional Regulation Of The Drosophila Anterior Determinant, Bicoid, John Mclaughlin

Dissertations, Theses, and Capstone Projects

In a wide variety of biological contexts, messenger RNA (mRNA) is known to have a complex and dynamic life cycle. In particular, the localization and translational control of mRNA are essential for proper development in eukaryotes. The fly Drosophila melanogaster is an excellent model for studying these processes. During D. melanogaster oogenesis, several mRNAs are trafficked and localized within the developing egg chamber, and regulated at the translational level to enable embryo patterning. One such mRNA, bicoid, is localized at the anterior of the oocyte and translated in the early embryo, where its encoded protein directs formation of the fly's …

Living With Fragile X Syndrome: Occupations As An Outcome Measure In A Clinical Trial, Kaylee E. Gothelf, Ty Duong, Ana Baldinger, Theresa Chase

Student Research Posters

The purpose of this study was to evaluate the use of semi-structured interviews as an outcome measure in a clinical trial for children with fragile X syndrome (FXS) ages 2-6. This qualitative approach was used to analyze twenty-five interviews of parents with children in a double-blind medication trial - sertraline or placebo. The aim was to assess occupational improvements in their child that may not have been detected with the use quantitative outcome measures alone. Results showed greater improvements in the sertraline group in areas of behavior, social participation, sensory-related behaviors, receptive language, education, family impact and therapeutic strategies. Our …

Feasibility & Discovery Using Fox System To Generate Gain-Of-Function Mutations With Hybrid Poplars, James Rauschendorfer

Dissertations, Master's Theses and Master's Reports

The Full-length complementary DNA OvereXpression (FOX) system is an approach to generating gain-of-function (GF) plants predominantly used for studying Arabidopsis. This approach inserts T-DNAs containing random full-length complementary DNA (fl-cDNA) with upstream promoter and downstream terminator into the host plant genome. Studies using this method report the success generating overexpression populations with high mutation rates. We choose to investigate the feasibility and effectiveness of this method using poplars. We suspected using a succulent xylem specific fl-cDNAs library would enrich the transformant poplars with mutants affected in traits specific to woody tissue development. We observed a characteristically high mutation rate …

Investigation On Genetic Modifiers Of Age At Onset Of Major Depressive Disorder, Huseyin Gedik

Theses and Dissertations

Major Depressive Disorder (MDD) is a complex multifactorial disorder, which would lead to disability. Environmental and genetic factors are involved in MDD etiology. The aim of this project was to identify loci modifying age at onset (AAO) of MDD using survival models after adjusting for Childhood Sexual Abuse (CSA). To achieve this aim, a dataset was made available by the China Oxford and VCU Experimental Research on Genetic Epidemiology (CONVERGE) consortium. The study population had 5,220 controls and 5,282 cases with MDD. We performed two univariate association analyses using Cox Proportional Hazard (Cox PH) models. These two are Full Sample …

Role Of Mitochondrial Beta-Oxidation In Ethanol Response: A Candidate Gene Study Using Caenorhabditis Elegans, Harini Pallikarana Tirumala

Theses and Dissertations

Alcohol use disorder (AUD) is the fourth leading cause of preventable death in the United States, and the fifth leading risk factor for premature death and disability, globally. There are currently very few treatment options for AUD and there is a need for effective preventive and treatment strategies for this condition. AUD risk has a significant hereditary component, with the contribution of genetic factors being estimated to be about 50%. The Davies-Bettinger laboratory uses C. elegans as a model organism to study the contribution of genetic factors in modulating neuronal responses to ethanol. In this project, we examined the role …

Pnpase In C. Elegans: Mutagenic Analysis To Complement Knockdown Studies, Danielle K. Seibert

Theses and Dissertations

PNPase is a gene implicated as a potential target for cancer therapy; human mutations also present with deafness, myopathies, and neuropathies. In this study, C. elegans was used to investigate the effect of knocking out PNPase in a whole animal. C. elegans knockdown studies have reported an extended lifespan via an increase in ROS production. Further noted are larger mitochondria and an increase in fzo-1 expression. Knockout animals previously constructed using CRISPR/Cas9 were used for this study. We aimed to confirm these findings validating previous studies. It was discovered that PNPase knockout animals demonstrated a similar lifespan extension that was …

Molecular Measurement Of Toxicity In Fish; Case Examples And Policy Implications, Jessica A. Freedman

Senior Honors Projects

Stormwater and oil are common urban contaminants that can be harmful to fish species. One way of recognizing exposed and impaired fish is by monitoring gene expression and gene induction. This study focused on the identification and validation of reference genes for measuring contaminant-induced changes in gene expression due to urban influence. In this study, reference genes (which are genes used to normalize data and remain consistent in varying exposures regardless of organism and tissue type) were established. Six genes were identified as reference genes (ef1a, wdtc1, mtm1, spop, rxrba and tuba1) from a longer list of potential …

Associations Of Single Nucleotide Polymorphisms In The Bovine Prolactin, Melatonin Receptor 1a, And Dopamine Receptor D2 Genes With Hair Coat Shedding Scores And Productivity Traits In Beef Cattle, Laura R. Meyer

Graduate Theses and Dissertations

Calving rate is a qualitative trait regulated by several genes and is strongly affected by the environment. With the development of biotechnology and gene identification, scientists are able to determine which genes affect these productivity traits to improve accurate selection decisions. Prolactin (PRL) has been associated with reproductive traits, melatonin receptor 1a (MTNR1A) has been associated with meat quality traits, and the dopamine receptor D2 (DRD2) gene has been associated with hair coat score (HCS) in cattle. Our objective was to determine associations between mutations in the PRL, MTNR1A, and DRD2 genes and cow-calf profitability traits. Genomic DNA was extracted …

Reflections On The Current State Of Healthcare Transition For Young Adult Women With Turner Syndrome: Strategies For Facilitating Autonomy And Self-Management, Molly Elizabeth Snyder

Theses and Dissertations

The transition to adult-centered healthcare is a critical period for emerging adults, especially those with special healthcare needs (SHCNs). Considering the ongoing medical monitoring necessary for women with Turner syndrome (TS), it is essential that the transition process be comprehensive and well-coordinated. The aims of this study were to invite young women with TS to reflect on their healthcare transition experiences, to explore participants’ perceived control of their medical management, and to identify ways in which genetic counselors can be involved in multidisciplinary healthcare teams. The hypotheses were that young women with TS are motivated to learn more about their …

Genetic Counseling For Alcohol Use Disorder: Assessment Of Need In Affected And At-Risk Populations, Fayth Michelle Kalb

Theses and Dissertations

Introduction: Alcohol use disorder (AUD) is highly heritable, yet there has been no investigation regarding the possible benefits of genetic counseling for AUD. This study assessed the beliefs individuals with and at risk for AUD have regarding recurrence risk and etiology of AUD, how the presence of the condition in themselves or their family history has affected their lifestyle decisions, and potential benefit from AUD genetic counseling. Methods: An online questionnaire was distributed through social media to support groups for AUD inviting adults 18 years and older with a personal or family history of AUD. Results: Of the 122 individuals …

The Undiagnosed Patient And The Diagnostic Odyssey: Current Genetic Counseling Practices And Perspectives, Amelia Cordell Wardyn

Theses and Dissertations

Patients seen in genetics clinics often endure a diagnostic odyssey in their search for answers for their medical symptoms. This time is not only challenging for patients and their families, but also for the genetic counselors who are trying to help the patients. Previous research has shown that parents of children with undiagnosed medical disorders have specific goals and reasons for wanting to find a diagnosis, and there are many difficulties faced by these parents. Genetic counselors often serve as a prominent figure during the diagnostic odyssey, but little known research has assessed the current practices of and impact that …

Characterization Of The Marine Sponge Amphimedon Compressa Microbiome Across A Spatial Gradient, Renee Michelle Potens

HCNSO Student Theses and Dissertations

Diverse and ecologically important microbial communities (microbiomes) are symbiotic within marine sponges. In this study, the microbiome of Amphimedon compressa from three sample locations (Broward and Dade Counties, Southeast Florida, USA and the Southern Caribbean, Bocas del Toro, Panama) is characterized using 16S rRNA Illumina sequencing. The predominant taxa are Proteobacteria and Cyanobacteria, as expected for Low Microbial Abundance sponges, accounting for over 53% of the total microbiome community. The numbers of Operational Taxonomic Units (OTUs) decrease from Broward County (2,900) to Dade County (2,300) and then Bocas del Toro (1,200). The correlates to a decreasing north-south gradient of …

The Effects Of Epigenetics On Stress Response, Kevin Suddarth

Themis: Research Journal of Justice Studies and Forensic Science

Despite the vast amount of resources at the disposal of humanity today, the intricacies of human biology are often a mystery. The chemical and biological products of the human genome have been well studied and documented, but many of the chemical and neurological pathways are missing quite a few details. The human stress response is one of the most primal and valuable functions of this code that developed as a self- preservation mechanism (Hans, 1975) to naturally increase the odds of procreation. However, this function is prone to overload, particularly in individuals with certain epigenetic traits instilled by early life …

Social And Scientific Implications Of Genetic Testing In The Digital Age, Yaruska A. Ordinola

Senior Honors Projects

From Mendel’s law of inheritance in the 19th century through Watson and Crick’s revolutionary observations of the double helix in the 20th century, genetics has been a fascinating and continuing topic of discussion in the field of science (Collins & McKusick, 2001). Major studies like the Human Genome Project (HGP), initiated in 1990 and completed in 2003, provided a starting point from which scientists could more thoroughly investigate the human condition on a genetic level. Arising from this study, personal genomics is considered a blooming field in genetics- in which rapidly developing technological advances are able to provide easier and …

Congenic And Functional Analysis Of Rat Mammary Cancer Susceptibility., Saasha Le

Electronic Theses and Dissertations

Breast cancer is a complex disease affected by genetic, epigenetic and environmental factors. The genetic architecture of breast cancer comprises of high to low penetrance alleles. Although low penetrance alleles associate with a small change in an individual’s risk to breast cancer, the total number of variants present and the high population frequency attributes to a much greater population based impact compared to rare high penetrance alleles. Animal models have been used to study these low penetrance modifier alleles in breast cancer. Different rat strains vary in their susceptibility to 7,12- dimethybenzanthracene (DMBA) induced mammary carcinogenesis, with the Wistar- Furth …

Unique Features Of A Global Human Ectoparasite Identified Through Sequencing Of The Bed Bug Genome, Joshua B. Benoit, Zach N. Adelman, Klaus Reinhardt, Amanda Dolan, Monica Poelchau, Emily C. Jennings, Elise M. Szuter, Richard W. Hagan, Hemant Gujar, Jayendra Nath Shukla, Fang Zhu, M. Mohan, David R. Nelson, Andrew J. Rosendale, Christian Derst, Valentina Resnik, Sebastian Wernig, Pamela Menegazzi, Christian Wegener, Nicolai Peschel, Jacob M. Hendershot, Wolfgang Blenau, Reinhard Predel, Paul R. Johnston, Panagiotis Ioannidis, Robert M. Waterhouse, Ralf Nauen, Corinna Schorn, Mark-Christoph Ott, Frank Maiwald, Subba R. Palli

Entomology Faculty Publications

The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host-symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome …

Building A History Of Horizontal Gene Transfer In E. Coli, Matthew Wilber

HMC Senior Theses

Bacteria's ability to pass entire genes between one another, a process called Horizontal Gene Transfer (HGT), has a major impact on bacterial evolution. In an ongoing project at Harvey Mudd, computational methods have been used to catalogue the HGT events that have impacted a group of closely related bacteria.

This thesis builds on that project, by improving our ability to identify gene families --- groups of genes in different strains that are related. Previously, similarity was measured only by comparing two genes' DNA sequences, ignoring their positions on the organism's DNA. Here, we leverage genes' relative position to make a …

The Role Of Rapgap1 In Sxl Activation In Drosophila Melanogaster, Katherine M. Barnes

Lewis Honors College Capstone Collection

The master switch of the sexual differentiation and dosage compensation pathway in Drosophila is the sex lethal gene, Sxl. The early promoter, SxlPe, is activated in females, resulting in female-specific splicing of later transcripts (notably the late Sxl transcript SxlPm), while inactive in males. Chromatin immunoprecipitation (ChIP) assays have previously shown association of two conventionally heterochromatin-localized proteins, HOAP and HP1, at SxlPe, and in situ hybridization as well as RT-PCR assays have confirmed a repressive role for HOAP and both repressive and activating roles for HP1. The mechanism for the activity shift of HP1 is currently unknown. Deletions in the …

Bois 412/812: Human Genetics—A Peer Review Of Teaching Project Benchmark Portfolio, Colin D. Meiklejohn

UNL Faculty Course Portfolios

This portfolio focuses on Human Genetics, an upper-division course taken primarily by biology majors to fulfill elective credit in their degree. This course studies the genetic basis for human variation, with the goal of placing this variation in the context of human evolutionary history and the consequences of this variation for medical understanding and treatments. In Human Genetics, students complete an original synthetic research paper on a human genetic disorder. Through writing this paper, students are expected to learn how to navigate electronic databases and online resources on human genetic diseases, and to read and synthesize the primary scientific literature. …

Yeast Integral Membrane Proteins Apq12, Brl1, And Brr6 Form A Complex Important For Regulation Of Membrane Homeostasis And Nuclear Pore Complex Biogenesis, Museer A. Lone, Aaron E. Atkinson, Christine A. Hodge, Stéphanie Cottier, Fernando Martínez-Montañés, Shelley Maithel, Laurent Mène-Saffrané, Cole Cole, Roger Schneiter

Dartmouth Scholarship

Proper functioning of intracellular membranes is critical for many cellular processes. A key feature of membranes is their ability to adapt to changes in environmental conditions by adjusting their composition so as to maintain constant biophysical proper- ties, including fluidity and flexibility. Similar changes in the biophysical properties of membranes likely occur when intracellular processes, such as vesicle formation and fusion, require dramatic changes in membrane curvature. Similar modifications must also be made when nuclear pore complexes (NPCs) are constructed within the existing nuclear membrane, as occurs during in- terphase in all eukaryotes. Here we report on the role of …

Development Of The Crispr/Cas9 System For Targeted Gene Disruption In Aspergillus Fumigatus, Kevin Fuller, Shan Chen, Jennifer J. Loros, Jay C. Dunlap

Dartmouth Scholarship

Low rates of homologous recombination have broadly encumbered genetic studies in the fungal pathogen Aspergillus fumigatus. The CRISPR/Cas9 system of bacteria has recently been developed for targeted mutagenesis of eukaryotic genomes with high effi- ciency and, importantly, through a mechanism independent of homologous repair machinery. As this new technology has not been developed for use in A. fumigatus, we sought to test its feasibility for targeted gene disruption in this organism. As a proof of principle, we first demonstrated that CRISPR/Cas9 can indeed be used for high-efficiency (25 to 53%) targeting of the A. fu- migatus polyketide synthase gene (pksP), …

Functional Analysis Of Synthetic Gene Circuits Controlling A Protein Pump In Yeast, Junchen Diao

Dissertations and Theses (Open Access)

Synthetic biology aims to build biological devices to understand living systems and explore new applications. Synthetic gene circuits such as genetic switches, oscillators and logic gates are at the core of many synthetic biology applications. These gene circuits often include a sensor/regulator protein capable to detect small molecules and then transduce them into a regulatory signal to generate measurable output. Similar signal transduction networks are also abundant in nature. However, in many natural and engineered scenarios, the output also affects the regulator/sensor protein. How such interactions between the regulator/sensor and the output affect synthetic gene circuit function has not been …

Polyq-Dependent Rna–Protein Assemblies Control Symmetry Breaking, Changhwan Lee, Patricia Occhipinti, Amy S. Gladfelter

Dartmouth Scholarship

Dendritic growth in fungi and neurons requires that multiple axes of polarity are established and maintained within the same cytoplasm. We have discovered that transcripts encoding key polarity factors including a formin, Bni1, and a polarisome scaffold, Spa2, are nonrandomly clustered in the cytosol to initiate and maintain sites of polarized growth in the fungus Ashbya gossypii. This asymmetric distribution requires the mRNAs to interact with a polyQ-containing protein, Whi3, and a Pumilio protein with a low-complexity sequence, Puf2. Cells lacking Whi3 or Puf2 had severe defects in establishing new sites of polarity and failed to localize Bni1 protein. Interaction …

Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raúl Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra Obregon-Tito, Leslie Neal, Cecil M. Lewis, Jr.

Human Biology Open Access Pre-Prints

Determining the origins of those buried within undocumented cemeteries is of incredible importance to historical archaeologists and in many cases, the nearby communities. In the case of Avondale Burial Place, a cemetery in Bibb County, Georgia, in use from 1820 to 1950, all written documentation of those interred within it has been lost. Osteological and archaeological evidence alone could not describe, with confidence, the ancestral origins of the 101 individuals buried there. In the present study, we utilize ancient DNA extraction methods to investigate the origins of Avondale Burial Place through the use of well-preserved skeletal fragments from 20 individuals …

Biological Significance Of Photoreceptor Photocycle Length: Vivid Photocycle Governs The Dynamic Vivid-White Collar Complex Pool Mediating Photo-Adaptation And Response To Changes In Light Intensity, Arko Dasgupta, Chen-Hui Chen, Changhwan Lee, Amy S. Gladfelter, Jay C. Dunlap, Jennifer J. Loros

Dartmouth Scholarship

Most organisms on earth sense light through the use of chromophore-bearing photoreceptive proteins with distinct and characteristic photocycle lengths, yet the biological significance of this adduct decay length is neither understood nor has been tested. In the filamentous fungus Neurospora crassa VIVID (VVD) is a critical player in the process of photoadaptation, the attenuation of light-induced responses and the ability to maintain photosensitivity in response to changing light intensities. Detailed in vitro analysis of the photochemistry of the blue light sensing, FAD binding, LOV domain of VVD has revealed residues around the site of photo-adduct formation that influence the stability …

An Inquiry-Infused Introductory Biology Laboratory That Integrates Mendel's Pea Phenotypes With Molecular Mechanisms, Philip Kudish, E. Schlag, Nicholas J. Kaplinsky

Biology Faculty Works

We developed a multi-week laboratory in which college-level introductory biology students investigate Mendel's stem length phenotype in peas. Students collect, analyze and interpret convergent evidence from molecular and physiological techniques. In weeks 1 and 2, students treat control and experimental plants with Gibberellic Acid (GA) to determine whether uncharacterized short mutant lines are GA responsive. These data allow students to place the mutation in the GA signal transduction pathway. During weeks 2 and 3, plants are genotyped for Mendel's "le" mutation using a derived cleaved polymorphic sequences (dCAPS) PCR assay. This laboratory allows students to make a direct connection between …

Spiritual Exploration In The Prenatal Genetic Counseling Session, Katelynn G. Sagaser

Dissertations and Theses (Open Access)

Religion and spirituality are important components of many individuals’ lives, and spiritual needs may present among persons receiving medical care. Spirituality has been demonstrated to be significant in the coping of women experiencing pregnancy complications (Breen et al. 2006; Price et al. 2007). To characterize the manner in which prenatal genetic counselors might address spiritual issues with their patients, we surveyed 283 patients receiving prenatal genetic counseling using the Brief RCope and a series of questions that examined interest in spiritual exploration. Counselors were concurrently surveyed to identify the spiritual language used within the session and the counselor’s perceived importance …

Origins Of An Unmarked Georgia Cemetery Using Ancient Dna Analysis, Andrew T. Ozga, Raul Y. Tito, Brian M. Kemp, Hugh Matternes, Alexandra J. Obregon-Tito, Leslie Neal, Cecil M. Lewis Jr.

Biology Faculty Articles

Determining the origins of those buried within undocumented cemeteries is of incredible importance to historical archaeologists and, in many cases, the nearby communities. In the case of Avondale Burial Place, a cemetery in Bibb County, Georgia, in use from 1820 to 1950, all written documentation of those interred within it has been lost. Osteological and archaeological evidence alone could not describe, with confidence, the ancestral origins of the 101 individuals buried there. In the present study, we used ancient DNA extraction methods in well-preserved skeletal fragments from 20 individuals buried in Avondale Burial Place to investigate the origins of the …

An Approach For Determining And Measuring Network Hierarchy Applied To Comparing The Phosphorylome And The Regulome, Chao Cheng, Erik Andrews, Koon-Kiu Yan, Matthew Ung, Daifeng Wang, Mark Gerstein

Dartmouth Scholarship

Many biological networks naturally form a hierarchy with a preponderance of downward information flow. In this study, we define a score to quantify the degree of hierarchy in a network and develop a simulated-annealing algorithm to maximize the hierarchical score globally over a network. We apply our algorithm to determine the hierarchical structure of the phosphorylome in detail and investigate the correlation between its hierarchy and kinase properties. We also compare it to the regulatory network, finding that the phosphorylome is more hierarchical than the regulome.