Other Genetics and Genomics Commons^™

Deconstructing Systemic Sclerosis Heterogeneity: From Patient Subtypes To Pathogenic Fibroblasts, Rezvan Parvizi

Dartmouth College Ph.D Dissertations

This thesis advances heterogeneity as the central barrier both to interpreting therapeutic response and to identifying the molecular regulators that drive fibrosis in systemic sclerosis (SSc). In SSc, heterogeneity is manifest at every level at which the disease can be measured: clinically, in the variable extent of skin and organ involvement; molecularly, in the distinct gene-expression programs that distinguish otherwise comparable patients; and cellularly, in the diverse fibroblast populations from which the fibrotic signal ultimately arises.

Leveraging longitudinal skin transcriptomics from a large cohort treated with mycophenolate mofetil (MMF), the first study demonstrates that intrinsic molecular subtypes are dynamic rather …

Dna Methylation Variation In Eastern Diamondback Rattlesnakes (Crotalus Adamanteus) On A Georgia Barrier Island, Megan Hoog

College of Graduate Studies: Theses & Dissertations

The Eastern Diamondback Rattlesnake (Crotalus adamanteus, EDB) is the largest rattlesnake in the world and is thought to be declining in many portions of its range. Genetic venom studies in the Southeast United States have shown evidence of fine-scale differences within two main geographic groups on Jekyll Island. My objective is to expand on this finding to determine if epigenetic mechanisms, specifically DNA methylation, varies among different populations of EDB in similar environments, age classes, and sexes. I collected EDB blood samples through a partnership with the Jekyll Island Authority and screened 44 individuals for epigenetic variation from …

Dna Methylation Analysis Is Used To Identify Novel Genetic Loci Associated With Circulating Fibrinogen Levels In Blood, Julie Hahn, Jan Bressler, Arce Domingo-Relloso, Ming-Huei Chen, Daniel L Mccartney, Alexander Teumer, Jenny Van Dongen, Marcus E Kleber, Dylan Aïssi, Brenton R Swenson, Jie Yao, Wei Zhao, Jian Huang, Yujing Xia, Michael R Brown, Ricardo Costeira, Eco J C De Geus, Graciela E Delgado, Dre'von A Dobson, Paul Elliott, Hans J Grabe, Xiuqing Guo, Sarah E Harris, Jennifer E Huffman, Sharon L R Kardia, Yongmei Liu, Stefan Lorkowski, Riccardo E Marioni, Matthias Nauck, Scott M Ratliff, Maria Sabater-Lleal, Tim D Spector, Pierre Suchon, Kent D Taylor, Florian Thibord, David-Alexandre Trégouët, Kerri L Wiggins, Gonneke Willemsen, Jordana T Bell, Dorret I Boomsma, Shelley A Cole, Simon R Cox, Abbas Dehghan, Andreas Greinacher, Karin Haack, Winfried März, Pierre-Emmanuel Morange, Jerome I Rotter, Nona Sotoodehnia, Maria Tellez-Plaza, Ana Navas-Acien, Jennifer A Smith, Andrew D Johnson, Myriam Fornage, Nicholas L Smith, Alisa S Wolberg, Alanna C Morrison, Paul S De Vries

Faculty, Staff and Student Publications

Background:

Fibrinogen plays an essential role in blood coagulation and inflammation. Circulating fibrinogen levels may be determined by inter-individual differences in DNA methylation at CpG sites, and vice versa.

Methods:

We performed an epigenome-wide association study (EWAS) of circulating fibrinogen levels in 18,037 White, Black, American Indian, and Hispanic participants representing 14 studies from the CHARGE consortium. Circulating leukocyte DNA methylation was measured in 12,904 participants using the Illumina 450K array, and in 5,133 participants using the EPIC array. Each study performed an EWAS of fibrinogen using linear mixed models adjusted for potential confounders. Study-specific results were combined using array-specific …

Roles Of Oxidative Stress And Dna Methylation In Cigarette Smoking-Induced Accelerated Acute Myeloid Leukemia Progression, Mary Figueroa

Dissertations and Theses (Open Access)

Acute myeloid leukemia (AML) is a commonly diagnosed cancer in smokers. When current or former smokers have AML, they have worse survival compared to never smoking patients. This has been observed clinically for decades, but then it is unknown how smoking leads to worsened AML survival. Smoking causes oxidative stress and altered DNA methylation that persists for decades in peripheral blood mononuclear cells, but these changes from smoking have not been evaluated in the context of AML. We hypothesize that smoking-induced molecular changes, including altered DNA methylation associated with poor AML prognosis, promote AML. We developed a novel model to …

Liquid Biopsies For Type 2 Diabetes Mellitus: Biomarkers For Disease Risk And Diagnosis, Stephanie Chidester

Dissertations

Background: Type 2 diabetes mellitus (T2DM) has reached epidemic proportions in the United States. There is a critical need for earlier and more effective screening and diagnostic tools. Innovative liquid biopsy technologies may play a key role in meeting this need. Liquid biopsies are a non-invasive, adjunctive tool for determining diagnosis, prognosis, and therapeutic response. This dissertation focuses on two potential applications of liquid biopsy technologies to T2DM: (1) epigenome-wide association studies to identify epigenetic markers of risk for T2DM, and (2) extracellular vesicle (EV)-based biomarker studies to identify and detect markers associated with T2DM development and progression. Dissertation studies: …

Latent Growth Model Approach To Characterize Maternal Prenatal Dna Methylation Trajectories, Dana Lapato

Theses and Dissertations

Background. DNA methylation (DNAm) is a removable chemical modification to the DNA sequence intimately associated with genomic stability, cellular identity, and gene expression. DNAm patterning reflects joint contributions from genetic, environmental, and behavioral factors. As such, differences in DNAm patterns may explain interindividual variability in risk liability for complex traits like major depression (MD). Hundreds of significant DNAm loci have been identified using cross-sectional association studies. This dissertation builds on that foundational work to explore novel statistical approaches for longitudinal DNAm analyses. Methods. Repeated measures of genome-wide DNAm and social and environmental determinants of health were collected up to six …