Genetics and Genomics Commons^™

This Is Just A Phase : The Impact Of Population Structure On Haplotype Phasing And Linkage Disequilibrium Measures At Functional Genetic Sites., Roxanne Kaaren Leiter

Electronic Theses and Dissertations

The block-like structure of the human genome has been the subject of many scientific papers and is of practical significance in large-scale genome-wide association studies. How stringent haplotype block boundaries are within and between populations has been the subject of ongoing debate within human population genetics. This thesis will contribute to the description of universal and population-specific haplotype blocks at functional sites, namely across the IL-10 gene family (including IL-10, IL-19, IL-20 and IL-24), which is involved in a number of immune system processes, and MAPKAP-K2, an adjacent and functionally significant kinase gene. Beyond the description of blocks across these …

Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. Mcclain, Timothy L. Cover

Veterinary Science Faculty Publications

Helicobacter pylori is a genetically diverse bacterial species that colonizes the stomach in about half of the human population. Most persons colonized by H. pylori remain asymptomatic, but the presence of this organism is a risk factor for gastric cancer. Multiple populations and subpopulations of H. pylori with distinct geographic distributions are recognized. Genetic differences among these populations might be a factor underlying geographic variation in gastric cancer incidence. Relatively little is known about the genomic features of African H. pylori strains compared to other populations of strains. In this study, we first analyzed the genomes of …

Population Structure Of Lethrinus Lentjan (Lethrinidae, Percoidei) Across The South China Sea And The Philippines Is Detected With Lane-Affected Radseq Data, Ellen E. Biesack

Biological Sciences Theses & Dissertations

Southeast Asia includes the Coral Triangle, a marine biodiversity hotspot that supports important fishery resources experiencing varied threats. Patterns of speciation and population structure in the Coral Triangle have been examined to test hypotheses relating to the historical geologic processes that may have influenced this biodiversity phenomenon. This study investigates the genetic population structure of the Pink-ear Emperor Snapper, Lethrinus lentjan (Lacepède, 1802), across the Philippines and the South China Sea. The species is fished throughout the Coral Triangle by subsistence and commercial fishers and their landings have been in decline for several years, which could be indicative of depleted …

Tracing The Genetic Footprints Of The Redbelly Yellowtail Fusilier, Caesio Cuning, Across Multiple Spatial And Evolutionary Scales, Amanda Susanne Ackiss

Biological Sciences Theses & Dissertations

Overfishing is one of the most pervasive threats to coral reef ecosystems, and management of these multi-species resources is hampered by limited species-specific population level information. The reefs in the western tropical Pacific Ocean, including the Coral Triangle, are the most bio-diverse in the world. Home to more than 400 million people, this region contains some of the most threatened coral reef ecosystems. Presented here is the first comprehensive analysis of the genetic structure of Caesio cuning, planktivorous fish inhabiting reefs in the Coral Triangle and western Pacific Ocean. Data from both classical Sanger and next-generation sequencing were analyzed …

Population Structure, Connectivity, And Phylogeography Of Two Balistidae With High Potential For Larval Dispersal: Balistes Capriscus And Balistes Vetula, Luca Antoni

Dissertations

The gray triggerfish (Balistes capriscus) and the queen triggerfish (Balistes vetula) are two exploited reef fish distributed in tropical and temperate shelf waters of the Atlantic Ocean and the Mediterranean Sea. Both species are highly sedentary as adults but disperse pelagic larvae for extended periods of time potentially allowing connectivity across long distances under the action of oceanic currents. In this work population structure, phylogeography, and migration patterns were examined in the two species and contrasted with predictions of larval transport based on surface circulation data. A total of 1,017 gray triggerfish from twelve sampling localities …

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 …

Determining The Reproductive Patterns Of The Titan Acorn Barnacle (Megabalanus Coccopoma) In Its Introduced Range, Isabel L. Moran Ms.

Honors College Theses

Invasive species are a significant conservation concern given their contribution to native species decline. The barnacle, Megabalanus coccopoma, is a common invasive species in tropical and subtropical regions of both the Pacific and Atlantic oceans. Little is known about the life history and ecology of M. coccopoma, and data on reproductive biology could provide valuable insight into its propensity to establish introduced populations. Most species of barnacle (including M. coccopoma) are hermaphroditic, but self-fertilization is rare in species studied to date. A recent genetic study of introduced M. coccopoma populations in the southeastern US showed high levels of …

Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr

College of Graduate Studies: Theses & Dissertations

Color polymorphism in aposematic mimicry systems is a perplexing phenomenon for evolutionary biologists, as theoretically the benefits of converging on a model phenotype should constrain the evolution of phenotypic diversity in these systems (i.e., color polymorphism should not occur). Nevertheless, color polymorphism in mimicry systems is prevalent throughout many taxa. In some of these systems, the evolution of color polymorphism results in the existence of non-mimetic morphs, such as those that are cryptic. The case of ground snakes (Sonora semiannulata) is unique in that color polymorphism encompasses both mimetic and cryptic morphs, as well as individual mimetic and …

A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt

College of Graduate Studies: Theses & Dissertations

The reticulated flatwoods salamander (RFS) is an endangered salamander with a unique life history. One of the largest known, best studied refuges for RFS is found on Eglin Air Force Base, and these RFS have been sampled and managed extensively since 2010. My thesis seeks to better understand RFS by using genetic techniques to address several unknowns, including: 1) determining the population structuring of RFS and the manageable units for species conservation, 2) estimating the size and status of populations, 3) understanding dispersal of RFS and factors that influence this, 4) exploring the breeding biology and recruitment patterns of RFS …

Development Of An In Silico Kir Genotyping Algorithm And Its Application To Population And Cancer Immunogenetic Analyses, Howard Rosoff

Dissertations and Theses (Open Access)

Gene content determination and variant calling in the complex KIR genomic region are useful for immune system function analysis, pathogenesis and disease risk factor elucidation, immunotherapy development, evolutionary investigations, and human migration modeling. Sequence-specific oligonucleotide and sequence-specific primer PCR methods are the de facto standards for KIR presence/absence identification, but the current platforms are unsuitable for SNP calling, impractical for KIR typing large cohorts of DNA samples, and inapplicable for typing repositories in which sequence data, but not cells or cell analytes, are available. Alternative typing methods, such as in silico sequence-based typing, can address the problems associated with amplicon-based …

Genome-Wide Differentiation In Closely Related Populations: The Roles Of Selection And Geographic Isolation, Rebecca Safran, Elizabeth Scordato, Matt Wilkins, Joanna K. Hubbard, B. R. Jenkins, Tomáš Albrecht, Samuel Flaxman, H. Karaardiç, Yoni Vortman, Arnon Lotem, Patrik Nosil, P. Pap, Sheng-Feng Shen, S.-F. Chan, T. L. Parchman, Nolan C. Kane

School of Biological Sciences: Faculty Publications

Population divergence in geographic isolation is due to a combination of factors. Natural and sexual selection may be important in shaping patterns of population differentiation, a pattern referred to as “isolation by adaptation” (IBA). IBA can be complementary to the well-known pattern of “isolation by distance” (IBD), in which the divergence of closely related populations (via any evolutionary process) is associated with geographic isolation. The barn swallow Hirundo rustica complex comprises six closely related subspecies, where divergent sexual selection is associated with phenotypic differentiation among allopatric populations. To investigate the relative contributions of selection and geographic distance to genome-wide differentiation, …

A Comparative Study Of Isolation In Headwater Fishes, Bjorn Victor Schmidt

Dissertations

Headwater resident fishes may be prone to a high rate of population fragmentation within river networks because large streams have habitat conditions outside of their preferred ecological niche and may limit gene flow in the dendritic ecological network. To investigate patterns of population structure, asymmetrical gene flow, and influences on genetic distance and isolation from connecting habitat pathways, species specific ecological traits, and basin scale characteristics, a multi-species, multi-regional study was performed. Six headwater species of fish from four taxonomic groupings were sampled for genetic material in three regions of paired neighbor drainages and then genotyped for eight microsatellite loci. …

Insights Into The Introduction Histories And Population Genetic Dynamics Of The Nile Monitor (Varanus Niloticus) And Argentine Black And White Tegu (Salvator Merianae) In Florida., Jared Price Wood

Electronic Theses and Dissertations

This dissertation examines the population genetic dynamics of two Florida invasives: the Nile monitor (Varanus niloticus) and Argentine black and white tegu (Salvator merianae). I also provide insights into the introduction histories of both species. This study was developed as part of a collaborative effort with the Florida Wildlife Commission to expand our knowledge of these highly detrimental, invasive lizards. All research activities involving animals and animal tissues were approved by the University of Louisville’s Institutional Animal Care and Use Committee (IACUC Proposal #: 12024). I start with a brief introduction into what makes invasive species …

Global Genetic Connectivity And Diversity In A Shark Of High Conservation Concern, The Oceanic Whitetip, Carcharhinus Longimanus, Cassandra L. Ruck

HCNSO Student Theses and Dissertations

The oceanic whitetip shark, Carcharhinus longimanus, is a circumtropical pelagic shark of high conservation concern (IUCN Red List: “Critically Endangered” in the Western North and Western Central Atlantic and “Vulnerable” globally). I present the first, population genetic assessment of the oceanic whitetip shark on a global scale, based on analysis of two mitochondrial genome regions (entire 1066-1067 bp control region and 784 bp partial ND4 gene), and nine nuclear microsatellite loci. No population structure was detected within the Western Atlantic. However, highly significant population structure was detected between Western Atlantic and Indo-Pacific Ocean sharks across all markers. Additionally, a …

A Mitochondrial Dna-Based Computational Model Of The Spread Of Human Populations, Peter Revesz

School of Computing: Faculty Publications

This paper presents a mitochondrial DNA-based computational model of the spread of human populations. The computation model is based on a new measure of the relatedness of two populations that may be both heterogeneous in terms of their set of mtDNA haplogroups. The measure gives an exponentially increasing weight for the similarity of two haplogroups with the number of levels shared in the mtDNA classification tree. In an experiment, the computational model is applied to the study of the relatedness of seven human populations ranging from the Neolithic through the Bronze Age to the present. The human populations included in …

Panmixia Across The Range Of The Assortatively Mating Lesser Snow Goose, Brent B. Horowitz

Electronic Theses and Dissertations

The Lesser Snow Goose has been shown to exhibit imprinted positive assortative mating on the basis of its color phases, blue and white, and it has been proposed that the geographic cline of the color phases reflects a historic allopatry of the phases. Using ddRAD-seq, thousands of SNPs were analyzed in both phases and in colonies across the range of the species to examine genetic evidence for separation of the color phases or along the two migratory pathways, which have also been hypothesized to be separate. These analyses did not reveal any genetic differentiation between the color phases nor by …

Isolation And Characterization Of Eight Polymorphic Microsatellites For The Spotted Spiny Lobster, Panulirus Guttatus, Nathan Truelove, Donald C. Behringer, Mark J. Butler Iv, Richard F. Preziosi

Biological Sciences Faculty Publications

Microsatellite sequences were isolated from enriched genomic libraries of the spotted spiny lobster, Panulirus guttatus using 454 pyrosequencing. Twenty-nine previously developed polymerase chain reaction primer pairs of Panulirus argus microsatellite loci were also tested for cross-species amplification in Panulirus guttatus. In total, eight consistently amplifying, and polymorphic loci were characterized for 57 individuals collected in the Florida Keys and Bermuda. The number of alleles per locus ranged from 8 to 20 and observed heterozygosities ranged from 0.409 to 0.958. Significant deviations from Hardy–Weinberg equilibrium were found in one locus from Florida and three loci from Bermuda. Quality control testing indicated …

A Gene-Based Association Method For Mapping Traits Using Reference Transcriptome Data, Eric R. Gamazon, Heather Wheeler, Kaanan P. Shah, Sahar V. Mozaffari, Keston Aquino-Michaels, Robert J. Carroll, Anne E. Eyler, Joshua C. Denny, Gtex Consortium, Dan L. Nicolae, Nancy J. Cox, Hae Kyung Im

Bioinformatics Faculty Publications

Genome-wide association studies (GWAS) have identified thousands of variants robustly associated with complex traits. However, the biological mechanisms underlying these associations are, in general, not well understood. We propose a gene-based association method called PrediXcan that directly tests the molecular mechanisms through which genetic variation affects phenotype. The approach estimates the component of gene expression determined by an individual’s genetic profile and correlates ‘imputed’ gene expression with the phenotype under investigation to identify genes involved in the etiology of the phenotype. Genetically regulated gene expression is estimated using whole-genome tissue-dependent prediction models trained with reference transcriptome data sets. PrediXcan enjoys …

Relative Abundances Of The Recently Introduced Barnacles, Megabalanus Coccopoma And An Unidentified Species Of Megabalanus, In The Southeastern U.S., Jennifer L. Tyson

Honors College Theses

ABSTRACT

Megabalanus coccopoma is a prominent invasive species off the coast of Georgia. Recently, among collected samples thought to be M. coccopoma, several individuals of an unidentified species of barnacle were found. The species has been identified as a Megabalanus species, but is still unidentified to the species level. Species identification is difficult due to morphological variation, inconsistent taxonomic keys, and unknown origin. In this study I developed a method to accurately distinguish M. coccopoma from the unidentified Megabalanus sp. using sequence differences in the mitochondrial Cytochrome Oxidase I (COI) gene. This study will provide an accurate estimate of …

Identification Of Whole Mitochondrial Genomes From Venezuela And Implications On Regional Phylogenies In South America, Esther J. Lee, D. Andrew Merriwether

Human Biology Open Access Pre-Prints

Recent studies have expanded and refined the founding haplogroups of the Americas using whole mitochondrial (mtDNA) genome analysis. In addition to pan-American lineages, a number of studies have identified specific variants that show higher frequencies in restricted geographical areas. In order to further characterize Native American maternal lineages and specifically examine local patterns within South America, we analyzed twelve maternally unrelated Yekuana whole mtDNA genomes from one village (Sharamaña) that include the four major Native American haplogroups A2, B2, C1, and D1. Our study proposes a reconfiguration of one subhaplogroup A2 (A2aa) that is specific to South America and identifies …

Fighting Microbial Drug Resistance: A Primer On The Role Of Evolutionary Biology In Public Health, Gabriel Perron, R. Inglis, Pleuni Pennings, Sarah Cobey

Biology Department Faculty Works

Although microbes have been evolving resistance to antimicrobials for millennia, the spread of resistance in pathogen populations calls for the development of new drugs and treatment strategies. We propose that successful, long-term resistance management requires a better understanding of how resistance evolves in the first place. This is an opportunity for evolutionary biologists to engage in public health, a collaboration that has substantial precedent. Resistance evolution has been an important tool for developing and testing evolutionary theory, especially theory related to the genetic basis of new traits and constraints on adaptation. The present era is no exception. The articles in …

Genetic Structure Of Ixodes Scapularis Say 1821 (Acari: Ixodidae), The Blacklegged Tick, By Microsatellite Analysis, John Ludwig

College of Graduate Studies: Theses & Dissertations

The blacklegged tick, Ixodes scapularis (Acari: Ixodidae) is the subject of intense research due to its economic importance from being a vector of several diseases. Previous studies have examined its taxonomic status and more recently, its genetic structure. This study embarked upon resolving the questions surrounding the genetic structuring of the tick, by using different molecular markers. Molecular data were first phylogenetically analyzed by using four different mitochondrial and nuclear markers (12SrDNA n=483, Dloop n=432, ITS2 n=156, Actin n=117). A Bayesian tree was inferred from the concatenated mitochondrial dataset, whereas nuclear gene markers were found to be uninformative. Nine microsatellites …

Estimating Migration Rates Between Populations Of Zostera Marina In The San Francisco Bay, Elizabeth S. Gutierrez

STAR Program Research Presentations

Eelgrass (Zostera marina) is a highly clonal marine angiosperm that can also reproduce sexually through flowering and seed formation. In a previous study, Fst values from six microsatellite loci suggested that a perennial San Francisco Bay subpopulation at Point Molate (Richmond, California) was able to recover from a drastic 2006 die-off through seed recruitment from neighboring eelgrass subpopulations, changing its reproductive strategy from clonal to sexual. Although Fst measures continue to be widely used in population genetics, the assumptions under which they operate are not always appropriate given certain circumstances, such small population sizes and/or asymmetrical migration rates. Our summer …

Human Diversity In Jordan: Polymorphic Alu Insertions In General Jordanian And Bedouin Groups, Daniela Zanetti, May Sadiq, Robert Carreras-Torres, Omar Khabour, Almuthanna Alkaraki, Esther Esteban, Marc Via, Pedro Moral

Human Biology Open Access Pre-Prints

Jordan, located in the Levant region, is a crucial area to investigate human migration between Africa and Eurasia. Even thought, the genetic history of Jordanians is far to be clarified including the origin of the Bedouins today resident in Jordan. Here, we provide new genetic data on autosomal independent markers in two Jordanian population samples (Bedouins and general population) in order to approach the genetic diversity inside this country and to give new information about the genetic position of these populations in the frame of the Mediterranean and Middle East area. The analyzed markers are 18 Alu polymorphic insertions characterized …

Concordant Phylogenetic Patterns Inferred From Mitochondrial And Microsatellite Dna In The Giant Clam Tridacna Crocea, Timery S. Deboer, Ma Rio Abdon Naguit, Mark V. Erdmann, Maria Carmen A. Ablan-Lagman, Ambariyanto, Kent E. Carpenter, Abdul Hamid A. Toba, Paul H. Barber

Biological Sciences Faculty Publications

The boring giant clam, Tridacna crocea Lamarck, 1819, is a CITES-listed bivalve that is declining due to overharvest and environmental degradation. Previous molecular studies in the Coral Triangle using mitochondrial DNA indicated the presence of deep phylogenetic divergence and strong phylogeographic structure across this region, suggesting the possibility of multiple cryptic species. In the present study, we compare data from non-recombining mitochondrial (mtDNA; cytochrome oxidase subunit 1, COI) and eight microsatellite loci to better understand patterns of genetic structure and species boundaries in T. crocea populations across Indonesia and the Philippines. Microsatellite loci and mtDNA data from 618 individuals representing …

Data From: Further Examination Of The Geographic Range Of Eriogonum Corymbosum Var. Nilesii (Polygonaceae), Mark W. Ellis, Paul G. Wolf, Shannon Bardot, James A. Walton, Carol A. Rowe, Sarah Kulpa, Karen E. Mock

Browse all Datasets

The buckwheat Eriogonum corymbosum is widely distributed throughout the southwestern United States, forming a complex of eight varieties. Eriogonum corymbosum var. nilesii is a primarily yellow-flowered taxon reported only from Clark County, Nevada. A previous genetic study by our research group found that variety nilesii is genetically distinct from other E. corymbosum varieties, based on a limited number of populations. Here, we assess genetic variation in 14 newly sampled yellow-flowered populations from southern Nevada, southern Utah, and northern Arizona, and compare them to genetic variation in six populations of previously determined E. corymbosum varieties. Of the new populations, we identified …

Genetic Variation, Local Adaptation And Population Structure In North American Red Oak Species, Quercus Rubra L. And Q. Ellipsoidalis E. J. Hill, Jennifer F. Lind-Riehl

Dissertations, Master's Theses and Master's Reports - Open

Forest trees, like oaks, rely on high levels of genetic variation to adapt to varying environmental conditions. Thus, genetic variation and its distribution are important for the long-term survival and adaptability of oak populations. Climate change is projected to lead to increased drought and fire events as well as a northward migration of tree species, including oaks. Additionally, decline in oak regeneration has become increasingly concerning since it may lead to decreased gene flow and increased inbreeding levels. This will in turn lead to lowered levels of genetic diversity, negatively affecting the growth and survival of populations. At the same …

Parentage Analysis And Conservation Genetics Educational Material For The Eastern Hellbender Salamander, Cryptobranchus Alleganiensis Alleganiensis, Sarah A. Chudyk

Master's Projects

Populations of the Eastern hellbender salamander, Cryptobranchus alleganiensis alleganiensis, are declining, making this a species of special concern in New York State and under consideration for Federal Endangered Species listing. As a result of this decline, the New York State Department of Environmental Conservation and the Buffalo Zoo initiated a headstarting program with an egg mass found in the Allegheny River drainage. The juveniles being raised by the Zoo will be released back into the watershed and so understanding the genetic diversity and parentage of these hellbenders will inform the reintroduction efforts. Furthermore, in order to determine how to …

Population Genetics And Ecology Of Regional Malaria Vectors In Amazonian Brazil, Sascha Naomi Mckeon

Legacy Theses & Dissertations (2009 - 2024)

Species complexes are common among anopheline mosquitoes, but only some members of complexes are disease vectors. Research involving overall patterns of divergence, phylogenetic relationships and population structure is partly driven by the operational need to be able to reliably distinguish component taxa that may be involved in malaria transmission. Anopheles triannulatus, An. nuneztovari and An. albitarsis are broadly distributed species complexes that contain local and regionally important malaria vectors, whose genetic diversity has been largely overshadowed by studies involving An. darlingi, the principal vector of Central and South America. I have analyzed the ecological suitability of habitats and geographical ranges …

Genetic Population Structure Of Us Atlantic Coastal Striped Bass (Morone Saxatilis), David T. Gauthier, Corinne A. Audemard, Jeanette E. L. Carlsson, Tanya L. Darden, Michael R. Denson, Kimberly S. Reece, Jens Carlsson

Biological Sciences Faculty Publications

Genetic population structure of anadromous striped bass along the US Atlantic coast was analyzed using 14 neutral nuclear DNA microsatellites. Young-of-the-year and adult striped bass (n = 1114) were sampled from Hudson River, Delaware River, Chesapeake Bay, North Carolina, and South Carolina. Analyses indicated clear population structure with significant genetic differentiation between all regions. Global multilocus F-ST was estimated at 0.028 (P < 0.001). Population structure followed an isolation-by-distance model and temporal sampling indicated a stable population structure more than 2 years at all locations. Significant structure was absent within Hudson River, whereas weak but significant genetic differences were observed between northern and southern samples in Chesapeake Bay. The largest and smallest effective striped bass population sizes were found in Chesapeake Bay and South Carolina, respectively. Coalescence analysis indicated that the highest historical gene flow has been between Chesapeake Bay and Hudson River populations, and that exchange has not been unidirectional. Bayesian analysis of contemporary migration indicated that Chesapeake Bay serves as a major source of migrants for Atlantic coastal regions from Albemarle Sound northward. In addition to examining population genetic structure, the data acquired during this project were capable of serving as a baseline for assigning fish with unknown origin to source region.