Genetics Commons^™

Investigation Of Genetic Alterations In Emt Suppressor, Dear1, Through Pan-Cancer Analysis And Ultra-Deep Targeted Sequencing In Ductal Carcinoma In Situ, Jacquelyn Reuther

Dissertations and Theses (Open Access)

Ductal carcinoma in situ (DCIS) is thought to be one of the earliest pre-invasive form of and non-obligate precursor to invasive ductal carcinoma (IDC). There is an urgent need to identify predictive and prognostic biomarkers for breast cancers with a heightened risk of progression from DCIS to IDC. Our laboratory has previously discovered a novel TRIM family member, DEAR1 (Ductal Epithelium Associated Ring Chromosome 1, annotated as TRIM62) within chromosome 1p35.1, that is mutated and homozygously deleted in breast cancer and whose expression is downregulated/lost in DCIS. Previous work has shown that DEAR1 is a novel tumor suppressor …

Genetics Of Obesity In Starr County, Texas Mexican Americans, Heather M. Highland

Dissertations and Theses (Open Access)

Currently, over two-thirds of Americans are classified as over-weight or obese. Obesity increases risk for many other diseases including type 2 diabetes, heart disease, stroke, and cancer, making obesity the largest public health problem in America and most other Westernized nations. Hispanics have a higher rate of both obesity and type 2 diabetes, making them a particularly interesting population in which to study obesity. For the last 33 years, the Starr County Health Studies has collected an array of phenotypes and biological samples from residents of Starr County, along Texas-Mexico border. This study includes 825 subjects who were not known …

Elucidating The Role Of Rumi And O-Glucosylation In The Drosophila Eye, Amanda Haltom

Dissertations and Theses (Open Access)

Rumi is a protein O-glucosyltransferase that adds the sugar O-glucose onto the serine in the target sequence C-S-X-S-(P/A)-C found within properly folded EGF repeats. It was first discovered to modify the Drosophila Notch extracellular domain and to be required for Notch signaling in a temperature dependent manner, but other targets of Rumi remained unknown. Several other proteins in the Drosophila proteome harbor multiple consensus sequence highly predictive of O-glucose, including the transmembrane protein Crumbs and the secreted protein Eyes shut (Eys). Both of these proteins are required for proper eye development and mutations in their human homologs …

Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh

Dissertations and Theses (Open Access)

In mammalian cells, DNA polymerase θ (POLQ) is an unusual specialized DNA polymerase whose in vivo function is under active investigation. The protein is comprised of an N-terminal helicase-like domain, a C-terminal DNA polymerase domain, and a large central domain that spans between the two. This arrangement is also found in the Drosophila Mus308 protein, which helps confer resistance to DNA interstrand crosslinking agents. Homologs of POLQ and Mus308 are found in eukaryotes, including plants, but a comparison of phenotypes suggests that not all of these genes are functional orthologs. Flies with defective Mus308 are sensitive to DNA interstrand crosslinking …

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 …

Evaluating The Nccn Clinical Criteria For Hereditary Breast And Ovarian Cancer Syndrome Genetic Testing, Caiqian Wu

Dissertations and Theses (Open Access)

Hereditary Breast and Ovarian Cancer (HBOC) syndrome predisposes females with a BRCA1 or BRCA2 mutation to an up to 85% lifetime risk for breast cancer and an up to 40% lifetime risk for ovarian cancer. It is crucial for individuals with HBOC to be identified to allow for proper screening, management, and identification of at-risk family members in order to reduce mortality. The National Comprehensive Cancer Network (NCCN) has established clinical guidelines for when to recommend BRCA1/2 testing. A retrospective chart review of 1123 M.D. Anderson Cancer Center breast cancer patients was performed in order to evaluate the positive predictive …

Impact Of Differentiation Status Of Kidney Progenitors In Wilms Tumor Development, Le Huang

Dissertations and Theses (Open Access)

Wilms tumor is one of the most common solid tumors in children. It is an embryonic cancer of the kidney and is thought to arise from undifferentiated renal mesenchyme. However, the differentiation status of cells in the mesenchyme that can give rise to Wilms tumors is unknown. Gene expression analysis of a large panel of Wilms tumor patients has identified different subsets of Wilms tumors that are distinct in their clinical outcomes and gene expression signatures. These subsets express specific genes that correspond to different stages of differentiation during renal development, suggesting that Wilms tumors may arise from transformed cells …

Genetic Predictors Of Metabolic Side Effects Of Diuretic Therapy, Jorge L. Del Aguila

Dissertations and Theses (Open Access)

Thiazide diuretics are a recommended first-line monotherapy for hypertension (i.e.SBP>140 mmHg or DBP>90 mmHg). Even so, diuretics are associated with adverse metabolic side effects, such as hyperlipidemia, hyperglycemia and hypokalemia which increase the risk of developing type II diabetes. This thesis used three analytical strategies to identify and quantify genetic factors that contribute to the development of adverse metabolic effects due to thiazide diuretic treatment. I performed a genome-wide association study (GWAS) and meta-analysis of the change in fasting plasma glucose and triglycerides in response to HCTZ from two different clinical trials: the Pharmacogenomic Evaluation of Antihypertensive Responses …

Utilizing Haplotypes For Sensitive Snp Array-Based Discovery Of Somatic Chromosomal Mutations, Selina M. Vattathil

Dissertations and Theses (Open Access)

Somatic copy-number (CN) gains and losses and copy-neutral loss of heterozygosity (CNLOH) frequently occur in tumors and play a major role in the progression of disease by altering gene dosage and unmasking deleterious recessive variants. Characterizing these mutations in an individual tumor sample is therefore critical for research on the relationship of specific mutations to disease outcome and for clinical decision-making based on mutations with known impact. A pervasive hindrance to sensitive detection of these mutations is genetic heterogeneity and high levels of contaminating normal cells in tumor samples, which limit the fraction of cells carrying informative mutations. The method …

The Association Between The Il-1 Pathway, Isaac C. Wun

Dissertations and Theses (Open Access)

Cutaneous malignant melanoma (CMM) is a potentially lethal malignancy that warrants attention and further research, as it is known to that there is an increasing rate of incidence in theUnited States, and it is also known that exposure to UV light is its most crucial risk factor, and family history of melanoma is also an important risk factor. Melanoma is an aggressive and lethal cancer in humans. There are an estimated new 132,000 melanoma cases annually worldwide, and the trend has doubled in the past 20 years. However, attempts to treat melanoma have encountered considerable resistance and remained ineffective. The …

Therapeutic Efficacy Of P53 Restoration In Mdm2-Overexpressing Tumors, Qin Li

Dissertations and Theses (Open Access)

The TP53 tumor suppressor is the most mutated gene in human cancers. Recent studies using genetically modified mouse models have shown that restoring the expression of wild-type p53 has led to tumor growth suppression in various types of tumors lacking p53. Other mechanisms, e.g. upregulation of Mdm2 levels, exist in tumors to inactivate the p53 pathway. Mdm2, an E3 ubiquitin-ligase that targets p53 for proteasomal degradation, is present at high levels in many tumors with wild-type p53. In this study, we probed the effects of restoring p53 activity in Mdm2-overexpressing tumors genetically using animal models. Here we demonstrated high levels …

Prkca: Identification Of A Novel Downstream Target Of Wt1, Devin Jones

Dissertations and Theses (Open Access)

Wilms tumor is a childhood tumor of the kidney arising from the undifferentiated metanephric mesenchyme. Tumorigenesis is attributed to a number of genetic and epigenetic alterations. In 20% of Wilms tumors, Wilms tumor gene 1 (WT1) undergoes inactivating homozygous mutations causing loss of function of the zinc finger transcription factor it encodes. It is hypothesized that mutations in WT1 result in dysregulation of downstream target genes, leading to aberrant kidney development and/or Wilms tumor. These downstream target genes are largely unknown, and identification is important for further understanding Wilms tumor development. Heatmap data of human Wilms tumor protein …

The Natural And Orthogonal Interaction (Noia) Models For Quantitative Traits (Qts) And Complex Diseases, Feifei Xiao

Dissertations and Theses (Open Access)

My dissertation focuses on developing methods for gene-gene/environment interactions and imprinting effect detections for human complex diseases and quantitative traits. It includes three sections: (1) generalizing the Natural and Orthogonal interaction (NOIA) model for the coding technique originally developed for gene-gene (GxG) interaction and also to reduced models; (2) developing a novel statistical approach that allows for modeling gene-environment (GxE) interactions influencing disease risk, and (3) developing a statistical approach for modeling genetic variants displaying parent-of-origin effects (POEs), such as imprinting.

In the past decade, genetic researchers have identified a large number of causal variants for human genetic diseases and …

Knowledge And Expectations Of Support People In Prenatal Genetic Counseling Sessions, Michelle A. Mcdougle

Dissertations and Theses (Open Access)

Prenatal genetic counseling patients have the ability to choose from a myriad of screening and diagnostic testing options, each with intricacies and caveats regarding accuracy and timing. Decisions regarding such testing can be difficult and are often made on the same day that testing is performed. Therefore, it is reasonable to consider that the support people brought to an appointment may have a role in the decision-making process. We aimed to better define this potential role by examining the incoming knowledge and expectations of support people who attended prenatal genetic counseling appointments.

Support people were asked to complete a survey …

Mismatch Repair Deficient Tumors Lacking Known Sporadic Causes: Are They All Due To Lynch Syndrome?, Katherine M. Dempsey

Dissertations and Theses (Open Access)

BACKGROUND: Mismatch repair deficient (MMRD) colorectal (CRC) or endometrial (EC) cancers in the absence of MLH1 promoter hypermethylation and BRAF mutations are suggestive of Lynch syndrome (LS). Positive germline genetic test results confirm LS. It is unclear if individuals with MMRD tumors but no identified germline mutation or sporadic cause (MMRD+/germline-) have LS.

HYPOTHESIS: Since LS is hereditary, individuals with LS should have a stronger family history of LS-related cancers than individuals with sporadic tumors. We hypothesized that MMRD+/germline- CRC and/or EC patients would have less suggestive family histories than LS CRC and/or EC patients.

METHODS: 253 individuals with an …

Identifying Genetic Variants And Characterizing Their Role In Clubfoot, Katelyn S. Weymouth

Dissertations and Theses (Open Access)

Clubfoot is a common, complex birth defect affecting 4,000 newborns in the United States and 135,000 world-wide each year. The clubfoot deformity is characterized by inward and rigid downward displacement of one or both feet, along with persistent calf muscle hypoplasia. Despite strong evidence for a genetic liability, there is a limited understanding of the genetic and environmental factors contributing to the etiology of clubfoot. The studies described in this dissertation were performed to identify variants and/or genes associated with clubfoot. Genome-wide linkage scan performed on ten multiplex clubfoot families identified seven new chromosomal regions that provide new areas to …

Genetic Analysis Of The Hippo Pathway In Mouse Liver, Li Lu

Dissertations and Theses (Open Access)

Cancer therapy and tumor treatment remain unsolved puzzles. Genetic screening for tumor suppressor genes in Drosophila revealed the Hippo-signaling pathway as a kinase cascade consisting of five core components. Disrupting the pathway by deleting the main component genes breaks the balance of cell proliferation and apoptosis and results in epithelial tissue tumorigenesis. The pathway is therefore believed to be a tumor suppressor pathway. However, a corresponding role in mammals is yet to be determined. Our lab began to investigate the tumor suppression function of the potent mammalian Hippo pathway by putting floxed alleles into the mouse genome flanking the functional-domain-expressing …

The Role Of The Arched Helicases In Exosome-Mediated Function, A. Alejandra Klauer

Dissertations and Theses (Open Access)

RNA processing and degradation are two important functions that control gene expression and promote RNA fidelity in the cell. A major ribonuclease complex, called the exosome, is involved in both of these processes. The exosome is composed of ten essential proteins with only one catalytically active subunit, called Rrp44. While the same ten essential subunits make up both the nuclear and cytoplasmic exosome, there are nuclear and cytoplasmic exosome cofactors that promote specific exosome functions in each of the cell compartments. To date, it is unclear how the exosome distinguishes between RNA substrates. We hypothesize that compartment specific cofactors may …

Tet1: A Unique Dna Demethylase For Maintenance Of Dna Methylation Pattern, Chunlei Jin

Dissertations and Theses (Open Access)

DNA methylation at the C5 position of cytosine (5-methylcytosine, 5mC) is a crucial epigenetic modification of the genome and has been implicated in numerous cellular processes in mammals, including embryonic development, transcription, X chromosome inactivation, genomic imprinting and chromatin structure. Like histone modifications, DNA methylation is also dynamic and reversible. However, in contrast to well defined DNA methyltransferases, the enzymes responsible for erasing DNA methylation still remain to be studied. The ten-eleven translocation family proteins (TET1/2/3) were recently identified as Fe(II)/2-oxoglutarate (2OG)-dependent 5mC dioxygenases, which consecutively convert 5mC into 5-hydroxymethylcytosine (5hmC), 5-formylcytosine and 5-carboxylcytosine both in vitro and in mammalian …

Knowledge, Attitudes, And Utilization Of Brca Testing Among Obstetricians And Gynecologists, Salma Nassef

Dissertations and Theses (Open Access)

Hereditary breast and ovarian cancer (HBOC) is an inherited cancer syndrome that is associated with mutations in the BRCA1 and BRCA2 genes. Carriers of BRCA mutations, both men and women, are at an increased risk for developing certain cancers. Carriers are most notably at an increased risk to develop breast and ovarian cancers; however an increased risk for prostate cancer, melanoma, and pancreatic cancers has also been associated with these mutations. In 2009 the American Congress of Obstetricians and Gynecologists (ACOG) released a practice bulletin stating that evaluating a patient’s risk for HBOC should be a routine part of obstetric …

Genetic Predictors Of Hyperglycemia Due To Hydrochlorothiazide Therapy, Jorge L. Del Aguila

Dissertations and Theses (Open Access)

Response to pharmacological treatment is variable among individuals. Some patients respond favorably to a drug while others develop adverse reactions. Early investigations showed evidence of variation in genes that code for drug receptors, drug transporters, and drug metabolizing enzymes; and pharmacogenetics appeared as the science that studies the relationship between drug response and genetic variation.

Thiazide diuretics are the recommended first-line monotherapy for hypertension (i.e. SBP>140 or DBP>90). Even so, diuretics are associated with adverse metabolic side effects, such as hyperglycemia, which increase the risk of developing type 2 diabetes. Published approaches testing variation in candidate genes (e.g. …

Effects Of Thymus Size And Involution On The Contribution Of Recent Thymic Emigrants To The Peripheral T Cell Pool, Michelle L. Bolner

Dissertations and Theses (Open Access)

The contribution of recent thymic emigrants (RTEs) to the peripheral naïve T cell population is necessary to maintain diversity of the T cell receptor (TCR) repertoire and produce immune responses against newly encountered antigens.

The thymus involutes with age, after irradiation or chemotherapy, and due to severe viral infections. Thymus involution results in decreased thymopoiesis and RTE output leading to a reduced diversity of peripheral T cells. This increases susceptibility to disease and impairs immune responsiveness to vaccines. Therefore, studies aimed at maintaining or regenerating thymic function are integral for maintaining and restoring peripheral TCR diversity.

Mice that express a …

Predictors Of Contralateral Breast Cancer In Brca Negative Women, Ann E. Simmons

Dissertations and Theses (Open Access)

Breast cancer is the most common cancer diagnosis and second leading cause of death in women. Risk factors associated with breast cancer include: increased age, alcohol consumption, cigarette smoking, white race, physical inactivity, benign breast conditions, reproductive and hormonal factors, dietary factors, and family history. Hereditary breast and ovarian cancer syndrome (HBOC) is caused by mutations in the BRCA1 and BRCA2 genes. Women carrying a mutation in these genes are at an increased risk to develop a second breast cancer. Contralateral breast cancer is the most common second primary cancer in patients treated for a first breast cancer. Other risk …

Gene By Bmi Interactions Influencing C-Reactive Protein Levels In European-Americans, Sarah Tudor

Dissertations and Theses (Open Access)

C-Reactive Protein (CRP) is a biomarker indicating tissue damage, inflammation, and infection. High-sensitivity CRP (hsCRP) is an emerging biomarker often used to estimate an individual’s risk for future coronary heart disease (CHD). hsCRP levels falling below 1.00 mg/l indicate a low risk for developing CHD, levels ranging between 1.00 mg/l and 3.00 mg/l indicate an elevated risk, and levels exceeding 3.00 mg/l indicate high risk. Multiple Genome-Wide Association Studies (GWAS) have identified a number of genetic polymorphisms which influence CRP levels. SNPs implicated in such studies have been found in or near genes of interest including: CRP, APOE, APOC, IL-6, …

Cocaine Dependence: The Role Of Serotonin Genes In, Lorena Maili

Dissertations and Theses (Open Access)

Animal studies have shown that behavioral responses to cocaine-related cues are altered by serotonergic medications. The effects of pharmacological agents on serotonin receptors 2a (5-HT2A) and 2c (5-HT2C), have yielded results suggesting that selective 5-HT2A antagonists and 5-HT2C agonists promote the disruption of cocaine-associated memories. One measure of cocaine related cues in humans is attentional bias, in which cocaine dependent individuals show greater response latency for cocaine related words than neutral words. Data from our laboratory shows that cocaine dependent subjects have altered attentional bias compared to controls. The purpose of this thesis was to investigate the role of the …

Cell Polarity Regulates Organ Growth Through The Hippo Pathway, Chiao-Lin Chen

Dissertations and Theses (Open Access)

Defects in apical-basal cell polarity and abnormal expression of cell polarity determinants are linked to human cancer. Loss of polarity is highly correlated with malignancy. In Drosophila, perturbation of apical-basal polarity, including overexpressing the apical determinant Crumbs, can lead to uncontrolled tissue growth. Cells mutant for the basolateral determinant scribble overproliferate and can form neoplastic tumors. Interestingly, scribble mutant clones that arise in wild-type tissues are eliminated and therefore do not manifest their tumorigenic potential. However, the mechanisms by which cell polarity coordinates with growth control pathways in developing organs to achieve appropriate organ size remain obscure.

To investigate …

Gene Discovery In Nonsyndromic Cleft Lip With Or Without Cleft Palate, Brett T. Chiquet

Dissertations and Theses (Open Access)

Nonsyndromic cleft lip with or without cleft palate (NSCLP), a common, complex orofacial birth defect that affects approximately 4,000 newborns each year in the United States, is caused by both genetic and environmental factors. Orofacial clefts affect the mouth and nose, causing severe deformity of the face, which require medical, dental and speech therapies. Despite having substantial genetic liability, less than 25% of the genetic contribute to NSCLP has been identified. The studies described in this thesis were performed to identify genes that contribute to NSCLP and to demonstrate the role of these genes in normal craniofacial development. Using genome …

Prevalence Of Premature Ovarian Failure In Women With Tuberous Sclerosis, Emily Gabitzsch

Dissertations and Theses (Open Access)

Tuberous Sclerosis Complex (TSC) is an autosomal dominant tumor suppressor disorder characterized by hamartomas, or benign growths, in various organ systems. Inactivating mutations in either the TSC1 or the TSC2 gene cause most cases of TSC. Recently, the use of ovarian specific conditional knock-out mouse models has demonstrated a crucial role of the TSC genes in ovarian function. Mice with complete deletion of Tsc1 or Tsc2 showed accelerated ovarian follicle activation and subsequent premature follicular depletion, consistent with the human condition premature ovarian failure (POF). POF is defined in women as the cessation of menses before the age of 40 …

Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn

Dissertations and Theses (Open Access)

The four basic helix-loop-helix myogenic transcription factors, myogenin, Myf5, MRF4, and MyoD are critical for embryonic skeletal muscle development. Myogenin is necessary for the terminal differentiation of myoblasts into myofibers during embryogenesis, but little is known about the roles played by myogenin in adult skeletal muscle function and metabolism. Furthermore, while metabolism is a well-studied physiological process, how it is regulated at the transcriptional level remains poorly understood. In this study, my aim was to determine the function of myogenin in adult skeletal muscle metabolism, exercise capacity, and regeneration. To investigate this, I utilized a mouse strain harboring the Myogflox …

Genetic Analysis Of The Function Of The Drosophila Doublesex-Related Factor Dmrt93b, Diana O'Day

Dissertations and Theses (Open Access)

DMRT (Doublesex and Mab-3 related transcription factor) proteins generally associated with sexual differentiation in many organisms share a common DNA binding domain and are often expressed in reproductive tissues. Aside from doublesex, which is a central factor in the regulation of sex determination, Drosophila possesses three different dmrt genes that are of unknown function. Because the association with sexual differentiation and reproduction is not universal and some DMRT proteins have been found to play other developmental roles we chose to further characterize one of these Drosophila genes. We carried out genetic analysis of dmrt93B, which was previously found to be …