Life Sciences Commons^™

Genetic Variants For Head Size Share Genes And Pathways With Cancer, Maria J Knol, Raymond A Poot, Tavia E Evans, Claudia L Satizabal, Aniket Mishra, Muralidharan Sargurupremraj, Sandra Van Der Auwera, Marie-Gabrielle Duperron, Xueqiu Jian, Isabel C Hostettler, Dianne H K Van Dam-Nolen, Sander Lamballais, Mikolaj A Pawlak, Cora E Lewis, Amaia Carrion-Castillo, Theo G M Van Erp, Céline S Reinbold, Jean Shin, Markus Scholz, Asta K Håberg, Anders Kämpe, Gloria H Y Li, Reut Avinun, Joshua R Atkins, Fang-Chi Hsu, Alyssa R Amod, Max Lam, Ami Tsuchida, Mariël W A Teunissen, Nil Aygün, Yash Patel, Dan Liang, Alexa S Beiser, Frauke Beyer, Joshua C Bis, Daniel Bos, R Nick Bryan, Robin Bülow, Svenja Caspers, Gwenaëlle Catheline, Charlotte A M Cecil, Shareefa Dalvie, Jean-François Dartigues, Charles Decarli, Maria Enlund-Cerullo, Judith M Ford, Barbara Franke, Barry I Freedman, Nele Friedrich, Melissa J Green, Simon Haworth, Catherine Helmer, Per Hoffmann, Georg Homuth, M Kamran Ikram, Clifford R Jack, Neda Jahanshad, Christiane Jockwitz, Yoichiro Kamatani, Annchen R Knodt, Shuo Li, Keane Lim, W T Longstreth, Fabio Macciardi, Outi Mäkitie, Bernard Mazoyer, Sarah E Medland, Susumu Miyamoto, Susanne Moebus, Thomas H Mosley, Ryan Muetzel, Thomas W Mühleisen, Manabu Nagata, Soichiro Nakahara, Nicholette D Palmer, Zdenka Pausova, Adrian Preda, Yann Quidé, William R Reay, Gennady V Roshchupkin, Reinhold Schmidt, Pamela J Schreiner, Kazuya Setoh, Chin Yang Shapland, Stephen Sidney, Beate St Pourcain, Jason L Stein, Yasuharu Tabara, Alexander Teumer, Anne Uhlmann, Aad Van Der Lugt, Meike W Vernooij, David J Werring, B Gwen Windham, A Veronica Witte, Katharina Wittfeld, Qiong Yang, Kazumichi Yoshida, Han G Brunner, Quentin Le Grand, Kang Sim, Dan J Stein, Donald W Bowden, Murray J Cairns, Ahmad R Hariri, Ching-Lung Cheung, Sture Andersson, Arno Villringer, Tomas Paus, Sven Cichon, Vince D Calhoun, Fabrice Crivello, Lenore J Launer, Tonya White, Peter J Koudstaal, Henry Houlden, Myriam Fornage, Fumihiko Matsuda, Hans J Grabe, M Arfan Ikram, Stéphanie Debette, Paul M Thompson, Sudha Seshadri, Hieab H H Adams

Journal Articles

The size of the human head is highly heritable, but genetic drivers of its variation within the general population remain unmapped. We perform a genome-wide association study on head size (N = 80,890) and identify 67 genetic loci, of which 50 are novel. Neuroimaging studies show that 17 variants affect specific brain areas, but most have widespread effects. Gene set enrichment is observed for various cancers and the p53, Wnt, and ErbB signaling pathways. Genes harboring lead variants are enriched for macrocephaly syndrome genes (37-fold) and high-fidelity cancer genes (9-fold), which is not seen for human height variants. Head size …

Unravelling The Genetic Basis Of Schizophrenia, Clara Casey, John F. Fullard, Roy D. Sleator

Department of Biological Sciences Publications

Neuronal development is a highly regulated mechanism that is central to organismal function in animals. In humans, disruptions to this process can lead to a range of neurodevelopmental phenotypes, including Schizophrenia (SCZ). SCZ has a significant genetic component, whereby an individual with an SCZ affected family member is eight times more likely to develop the disease than someone with no family history of SCZ. By examining a combination of genomic, transcriptomic and epigenomic datasets, large-scale ‘omics’ studies aim to delineate the relationship between genetic variation and abnormal cellular activity in the SCZ brain. Herein, we provide a brief overview of …

Deciphering The Functional Connections Between The Nuclear Paraspeckle And Rad51 Homologous Recombination Proteins Using A Yeast Protein Interaction System, Eric J. Nutz

Senior Theses

Homologous recombination (HR) is a repair pathway for DNA double-stranded breaks. Mutations in HR genes contribute to genomic instability and increase the prevalence of cancer. Exploiting HR deficiency in tumor cells has led to improved synthetic lethality outcomes. RAD51 paralogue protein complexes are known to be involved with HR. Proteomic analysis of RAD51 paralogues reveals a connection to the nuclear paraspeckle. A paraspeckle is a little-known, specialized organelle found in the interchromatin space of the nucleus in mammalian cells. Its three central protein components include SFPQ, NONO, and PSPC1. RAD51D is an HR protein shown previously to interact with SFPQ …

A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen

Cal Poly Humboldt theses and projects

Physical barriers to gene flow are the traditional evidence for species divergence. Conversely, there has been increasing acknowledgment of speciation in the face of gene flow as an evolutionary process. Budding speciation involves peripheral populations adapting to local ecological conditions, thereby budding off from a widespread progenitor species. Budding speciation is distinguished by ecological divergence and is generally evidenced by asymmetrical range size and nested phylogenetic relationships of sister species. The narrow endemic Abronia villosa var. aurita is adapted to montane sandy washes adjacent to its widespread sister variety, the desert dwelling var. villosa. Here, I tested the hypothesis …

The Genetic Basis Of Two Reproductive Traits In Monkeyflowers: Stigma Closure And Corolla Carotenoids, Rachel Anne Halperin

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Abstract

The interactions between pollinators and flowers have long been a driving force for the evolution of many physical floral traits. Traits such as flower shape, size, color, and smell are just some of these traits that evolve because of these interactions. This evolution does not only occur in the more obvious morphological floral traits, however, but also in more subtle traits like touch sensitive stigma closure. In hundreds of Lamiales species, the bilobed stigma, the organ that receives pollen from pollinators, closes rapidly upon touch. Theory and experiments show that this novel dynamic reproductive trait increases pollen export and …

Soybean Genetics, Genomics, And Breeding For Improving Nutritional Value And Reducing Antinutritional Traits In Food And Feed, William M. Singer, Yi-Chen Lee, Zachary Shea, Caio Canella Vieira, Dongho Lee, Xiaoying Li, Mia Cunicelli, Shaila S. Kadam, Mohammad Amir Waseem Khan, Grover Shannon, M. A. Rouf Mian, Henry T. Nguyen, Bo Zhang

Agriculture Faculty Publications

Soybean [Glycine max(L.) Merr.] is a globally important crop due to its valuable seed composition, versatile feed, food, and industrial end-uses, and consistent genetic gain. Successful genetic gain in soybean has led to widespread adaptation and increased value for producers, processors, and consumers. Specific focus on the nutritional quality of soybean seed composition for food and feed has further elucidated genetic knowledge and bolstered breeding progress. Seed components are historical and current targets for soybean breeders seeking to improve nutritional quality of soybean. This article reviews genetic and genomic foundations for improvement of nutritionally important traits, such as protein and …

Towards Understanding The Interactions Between Ospreys And Human-Made Structures In The Tennessee River Valley, Natasha Karina Murphy

Theses and Dissertations

Raptor nests on human-built structures represent a significant source of conflict as they can result in bird mortality, fires, structure damage, service distribution, or power outages when falling nest materials or animals connect with energized conductors. Power companies, such as the Tennessee Valley Authority (TVA), wish to mitigate these conflicts to avoid service disruptions. In this dissertation, I present my work towards understanding and mitigating the interactions between Ospreys (Pandion haliaetus) and human-made structures. To achieve this, I explored multiple elements of conflict identification, monitoring, and basic ecology of the target species to better inform conflict mitigation. In Chapter I, …

Engaging Students In A Genetics Course-Based Undergraduate Research Experience Utilizing Caenorhabditis Elegans In Hybrid Learning To Explore Human Disease Gene Variants, Natalie Forte, Virginia Veasey, Bethany Christie, Amira Carter, Marli Hanks, Alan Holderfield, Taylor Houston, Anil Challa, Ashley Turner

Research, Publications & Creative Work

Genetic analysis in model systems using bioinformatic approaches provides a rich context for a concrete and conceptual understanding of gene structure and function. With the intent to engage students in research and explore disease biology utilizing the nematode Caenorhabditis elegans model, we developed a semester-long course-based undergraduate research experience (CURE) in a hybrid (online/in-person) learning environment—the gene-editing and evolutionary nematode exploration CURE (GENE-CURE). Using a combination of bioinformatic and molecular genetic tools, students performed structure-function analysis of disease-associated variants of uncertain significance (VUS) in human orthologs. With the aid of a series of workshop-style research sessions, students worked in teams …

The Detection Of Putative Recessive Lethal Haplotypes In Irish Sheep Populations, Rory Mcauley

ORBioM (Open Research BioSciences Meeting)

In livestock populations, recessive lethal alleles are a known contributor to poor reproductive performance due to embryonic death in homozygous individuals. Despite their lethal effect in the recessive form, these alleles may be maintained at high frequencies among carrier animals because of their positive pleiotropic effects on economically important traits. Although several such recessive alleles have been identified in cattle and pig populations, limited studies have been completed in sheep, and none within Irish sheep populations. Genotype data for 69,034 animals from five major Irish sheep breeds genotyped on a variety of panels was available for this study. Only animals …

Estimating Heritability Explained By Local Ancestry And Evaluating Stratification Bias In Admixture Mapping From Summary Statistics, Tsz Fung Chan, Xinyue Rui, David V Conti, Myriam Fornage, Mariaelisa Graff, Jeffrey Haessler, Christopher Haiman, Heather M Highland, Su Yon Jung, Eimear E Kenny, Charles Kooperberg, Loic Le Marchand, Kari E North, Ran Tao, Genevieve Wojcik, Christopher R Gignoux, Charleston W K Chiang, Nicholas Mancuso

Journal Articles

The heritability explained by local ancestry markers in an admixed population (h

The Use Of Prognostic Markers To Predict Disease Progression And Clinical Outcome In Monoclonal Gammopathy Of Undetermined Significance, Smouldering Multiple Myeloma And Multiple Myeloma., Róisín C. Mcmonagle

International Undergraduate Journal of Health Sciences

Multiple Myeloma (MM) is an incurable plasma cell malignancy with a complex and incompletely understood molecular pathogenesis. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smouldering Multiple Myeloma (SMM) precede MM, with variable risks and rates of disease progression. The continuing high relapse and death rate in MM cases has prompted research into more accurate prognostic markers to predict progression from MGUS and SMM to MM, as well as identify MM cases with aggressive disease, in order to begin early, targeted and effective therapeutic intervention. Many studies have focused on utilising current markers more effectively, including M-protein, serum-free light chain ratio, …

Characterization Of The Immunoglobulin Lambda Chain Across Diverse Human Populations., William Gibson

Electronic Theses and Dissertations

The adaptive immune system relies on a diverse set of over one hundred immunoglobulin (IG) genes across three genomic loci that are variably combined to form antibodies (Ab). The IG Lambda locus is one of two loci which encodes the IG light chain. The complexity of the IGL locus severely limits the effective use of standard short-read sequencing, limiting our knowledge of population diversity in these loci. We leveraged single molecule real-time (SMRT) long-read sequencing in conjunction with IGL-targeted DNA capture to develop the method IG-Cap for accurate and high-throughput sequencing of the IGL locus. We benchmarked this method using …

Annotation Of Non-Model Species’ Genomes, Taiya Jarva

Master's Theses

The innovations in high throughput sequencing technologies in recent decades has allowed unprecedented examination and characterization of the genetic make-up of both model and non-model species, which has led to a surge in the use of genomics in fields which were previously considered unfeasible. These advances have greatly expanded the realm of possibilities in the fields of ecology and conservation. It is now possible to the identification of large cohorts of genetic markers, including single nucleotide polymorphisms (SNPs) and larger structural variants, as well as signatures of selection and local adaptation. Markers can be used to identify species, define population …

Reverse Genetics: Downregulating Chk-1 And Fasn-1 In The Gonads Of C. Elegans, Sam Thompson

Undergraduate Theses

Despite its widespread use in research, the model organism C. elegans has several biological processes like gonadal development with potentially unexplored genetic regulators. Previous transcriptome analysis has identified several genes that are upregulated in a specific tissue or sex during the development of the somatic gonad in C. elegans (Kroetz et al. 2015) that have not been previously connected to this process. Of these genes, this research is concerned with chk-1 and fasn-1. Abrogating the expression of these genes in gonadal tissue during gonadogenesis could cause a change in phenotype for affected C. elegans that would aid in understanding these …

Understanding Host-Microbe Interactions In Maize Kernel And Sweetpotato Leaf Metagenomic Profiles., Alison K. Adams

Doctoral Dissertations

Functional and quantitative metagenomic profiling remains challenging and limits our understanding of host-microbe interactions. This body of work aims to mediate these challenges by using a novel quantitative reduced representation sequencing strategy (OmeSeq-qRRS), development of a fully automated software for quantitative metagenomic/microbiome profiling (Qmatey: quantitative metagenomic alignment and taxonomic identification using exact-matching) and implementing these tools for understanding plant-microbe-pathogen interactions in maize and sweetpotato. The next generation sequencing-based OmeSeq-qRRS leverages the strengths of shotgun whole genome sequencing and costs lower that the more affordable amplicon sequencing method. The novel FASTQ data compression/indexing and enhanced-multithreading of the MegaBLAST in Qmatey allows …

Understanding The Relationship Between B Chromosomes And Nondisjunction In Drosophila Melanogaster, Ayushi Patel

Honors Scholar Theses

B chromosomes are supernumerary, heterochromatic genetic elements that are found in hundreds of different plant and animal species. Recently, B chromosomes were discovered in a stock of Drosophila melanogaster and are carried at a high copy number of 10-12 B chromosomes per cell. B chromosomes are not known to carry any active genes, but when placed in a wild-type genetic background, they cause a significant increase in the frequency of chromosome 4 missegregation during meiosis. This project aimed to understand the relationship between a female’s B chromosome copy number and how often she passes on too many (or too few) …

Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw

Dissertations & Theses (Open Access)

Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …

Gonads Without Glp-1: Silencing Glp-1 In The Male Somatic Gonad In Caenorhabditis Elegans, Matthew Titus

Undergraduate Theses

In C. elegans, the gene glp-1 encodes for a Notch receptor called GLP-1, one of two found in C. elegans’ genome. The gene has been previously implicated in the development of the hermaphroditic germline as well as playing a role in the mitosis/meiosis decision. Genetic screening has further identified it as potentially playing a role in the development of the male somatic gonad, making it an ideal candidate for a reverse genetic. We did this by silencing glp-1 and observing if any alterations to the gonad’s phenotype occur.

Normally this could be done by performing a gene knockout. …

Understanding The Expression And Role Of Pros-1 In The Male Gonad Of C. Elegans, Jack Bozik

Undergraduate Theses

The gene pros-1 is a transcription factor that is highly expressed within neuronal sheath cells, glial cells, and excretory canal cells. pros-1 plays a role in cell determination of those cell types in the nematode C. elegans, which promotes organismal development. But the degree to which pros-1 presence is important is still not fully understood, because there are many genes involved in development that when mutated or damaged can result in unexpected phenotypes or even total loss of function to a certain developmental mechanism. What makes pros-1 valuable to research is that it is a functional homologue to a …

Epigenetics In Forensic Science, Reagan Faunce

Honors Projects

DNA methylation can be useful for forensic scientists because it can be used to differentiate between the DNA of identical twins, determine the age of a contributor of a DNA sample, and help us understand the actions and tendencies of violent criminals. Research shows that DNA methylation changes over time and can be caused by traumatic events, suggesting that methylation increases with age. Prior studies of DNA methylation at the promoters of the EDARADD, TOM1L1, and NPTX2 genes have been able to predict age within 5.2 years and a study of the ASPA, EDARADD, PDE4C, and ELOVL2 genes predicted age …

The Genomics Of Autism-Related Genes Il1rapl1 And Il1rapl2: Insights Into Their Cortical Distribution, Cell-Type Specificity, And Developmental Trajectories, Jacob Weaver

MUSC Theses and Dissertations

Neuropsychiatric disorders have a significant impact on modern society. These disorders affect a large percentage of the population: schizophrenia has a world-wide prevalence of 1% and autism spectrum disorders (ASD) affects 1 in 59 school-aged children in the US. There is substantial evidence that most neuropsychiatric disorders have a genetic component. Thus, with the advent of high throughput sequencing much effort has gone into identifying genetic variants associated with these disorders. The emerging picture from these studies is a complex one where hundreds of genes with small effects interact with a varied landscape of common variants to result in disease. …

Gaming To Learn Genetics, Sarah Wolfe

Undergraduate Honors Thesis Projects

Digital game-based learning is an alternative to traditional lecture learning. It involves active engagement with concepts in a digital game setting and can apply to a variety of subjects, including STEM fields. We examined this type of learning in the context of an undergraduate introductory genetics course: specifically, use of a genetics video game for teaching. There were two groups: an experimental group that played the genetics game Geniventure, and a control group that read and studied Powerpoint lecture slides. Both groups took a pretest and posttest, as well as completed an I/D (interest/deprivation) scale and workload scale. There …

Protocol To Identify The Core Gene Supported By An Essential Gene In E. Coli Bacteria Using A Genome-Wide Suppressor Screen, Isao Masuda, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

We describe here a genome-wide screening approach to identify the most critical core reaction among a network of many that are supported by an essential gene to establish cell viability. We describe steps for maintenance plasmid construction, knockout cell construction, and phenotype validation. We then detail isolation of suppressors, whole-genome sequencing analysis, and reconstruction of CRISPR mutants. We focus on E. coli trmD, which encodes an essential methyl transferase that synthesizes m1G37 on the 3'-side of the tRNA anticodon. For complete details on the use and execution of this protocol, please refer to Masuda et al. (2022).

Paternal Ages And Genetic Diseases And Congenital Anomalies, Neda Hamood

The Pegasus Review: UCF Undergraduate Research Journal

he purpose of this research is to investigate the link between Advanced Paternal Ages (APA) (i.e., APA ≥ 35 years and APA ≥ 50 years) and genetic diseases and congenital anomalies. Currently, the relationship between both APA and genetic diseases and congenital anomalies remains unclear. There is room for improvement, however, to investigate systematically the relationship between specific congenital anomalies in newborns and APA. More recently, the link between APA (as opposed to existing studies analyzing Advanced Maternal Age alone) and genetic diseases has been recognized by researchers, epidemiologists, and various health experts. Thus, this study serves to examine the …

Multi-Ancestry Genome-Wide Association Analyses Improve Resolution Of Genes And Pathways Influencing Lung Function And Chronic Obstructive Pulmonary Disease Risk, Nick Shrine, Abril G. Izquierdo, Jing Chen, Richard Packer, Robert J. Hall, Anna L. Guyatt, Chiara Batini, Rebecca J. Thompson, Chandan Puvuluri, Vidhi Malik, Brian D. Hobbs, Matthew Moll, Wonji Kim, Ruth Tal-Singer, Per Bakke, Katherine A. Fawcett, Catherine John, Kayesha Coley, Noemi Nicole Piga, Sinjini Sikdar, Martin D. Tobin, Et Al.

Mathematics & Statistics Faculty Publications

Lung-function impairment underlies chronic obstructive pulmonary disease (COPD) and predicts mortality. In the largest multi-ancestry genome-wide association meta-analysis of lung function to date, comprising 580,869 participants, we identified 1,020 independent association signals implicating 559 genes supported by ≥2 criteria from a systematic variant-to-gene mapping framework. These genes were enriched in 29 pathways. Individual variants showed heterogeneity across ancestries, age and smoking groups, and collectively as a genetic risk score showed strong association with COPD across ancestry groups. We undertook phenome-wide association studies for selected associated variants as well as trait and pathway-specific genetic risk scores to infer possible consequences of …

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, …

Molecular Genetic Studies Of Horses, Especially With Reference To Aggrecan And Dwarfism, John Edmund Eberth

Theses and Dissertations--Veterinary Science

This work consists of studies on dwarfism in Miniature horses and a study on breakdowns in Thoroughbreds in relation to gene aggrecan. A correction of the description and designation of D3 dwarf variant in aggrecan (ACAN) from the master’s thesis Chondrodysplasia-like dwarfism in the Miniature horse (2013). Commercial sequencing showed previous sequencing reads presented an artifact and not a single base deletion. Analysis showed a single base missense mutation in exon 8 identified as D3* was the actual cause. Multiple alleles of ACAN associated with chondrodysplastic dwarfism in Miniature horses by Eberth et al. (2018), corrected the …

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 …

Extension Of The Ergot Alkaloid Gene Cluster, Samantha Joy Fabian

Graduate Theses, Dissertations, and Problem Reports

Specialized metabolites produced by fungi impact human health. A large portion of the pharmaceuticals currently on the market are derived from metabolites biosynthesized by microbes. Ergot alkaloids are a class of fungal metabolites that are important in the interactions of environmental fungi with insects and mammals and also are used in the production of pharmaceuticals. In animals, ergot alkaloids can act as partial agonists or antagonists at receptors for 5-hydroxytryptamine (serotonin), dopamine, and noradrenaline as ergot alkaloids have chemical structures similar to those neurotransmitters. Therefore, they affect insects and mammals that consume them and can be used to produce drugs …

Examining Genetically-Informed Etiologic Models Of Co-Occurring Posttraumatic Stress Disorder And Recreational Cannabis Use Among College Students, Terrell A. Hicks

Theses and Dissertations

The college years encompass a period of increased risk recreational cannabis use (RCU), as well as a time of increased risk for trauma exposure and developing posttraumatic stress disorder (PTSD). Given the high co-occurrence between RCU and PTSD, and the potentially negative consequences of the two (e.g., worse academic outcomes), there is a need to understand the etiologic mechanisms of these commonly co-occurring conditions. Two primary phenotypic models exist: self-medication model (i.e., PTSD to RCU) and the high-risk model (i.e., RCU to PTSD). To date, there are two existing studies longitudinally examining the etiologic models proposed to explain co-occurring RCU …