Digital Commons Network^™

Resolving The Longitudinal Triglyceride Phenotype Of Heterozygous Lpl And Apo A-V Deficiency, Shehan D. Perera

Electronic Thesis and Dissertation Repository

Hypertriglyceridemia (HTG) is a risk factor for cardiovascular disease. However, only the triglyceride (TG) phenotype produced by biallelic loss-of-function (LOF) variants in the canonical TG metabolism genes is well understood. The TG phenotype produced by monoallelic LOF variants is poorly understood. We aimed to evaluate the TG phenotype associated with monoallelic LOF variants in the canonical TG metabolism genes.

Next-generation sequencing panel was employed to identify patients heterozygous for LOF variants in two of the canonical TG metabolism genes LPL and APOA5, followed by chart review to determine baseline and longitudinal TG phenotype in these patients.

My findings suggest …

Investigation Of Neurotransmitter’S Knockdown Effect On Drosophila Melanogaster Female Aggression, Asil N. El Galad

Undergraduate Student Research Internships Conference

Drosophila melanogaster (D. melanogaster) is a popular model organism in neurobiology. While aggression has been studied heavily in male drosophila, there's minimal research on aggression in female drosophila. Neurotransmitters influencing aggressive behaviour in female D. melanogaster are poorly understood. Various neurotransmitters such as dopamine, octopamine, and serotonin influence aggression in D. melanogaster Further investigation of the role of neurotransmitters on aggression is thus important. The purpose of our experiment is to observe the effect of the knockdown of dopamine, octopamine and glutamate on aggression in female D. melanogaster.

The Molecular Landscape Of Early-Stage Breast Cancer With Lymph Node Metastasis, Farhad Ghasemi

Electronic Thesis and Dissertation Repository

Axillary lymph nodes (ALNs) are the primary site of metastasis in breast cancer, and their involvement has implications in disease staging, prognostication, and treatment decisions. A non-invasive modality of assessing the risk of ALN metastasis can improve care in patients with early-stage breast cancer by omitting the morbidity and costs associated with axillary surgery.

This thesis explores the molecular landscape of early-stage breast cancers with ALN metastasis and shows the potential of tumour molecular signatures in predicting ALN involvement. After a systematic review of the literature, we use data from The Cancer Genome Atlas (TCGA) to develop molecular signatures correlated …

My Summer Working With Two-Spotted Spider Mites, Renée A. Smith

Undergraduate Student Research Internships Conference

Two-spotted spider mites are a polyphagous pest, capable of eating a magnitude of food crops which causes a large problem for Canadian agriculture. Their ability to consume various crops stems from their ability to adapt to various chemical defence mechanisms. This ability allows them to acquire resistance to many commonly used pesticides. This has resulted in large infections in Canadian farms with few options to prevent the pests from affecting crop yields. Take a look at my project if you'd like to see how the Grbic lab is working to combat this issue using genetic engineering techniques!

Rna-Interference As A Topical Pesticide, Eleanor Khochaba

Undergraduate Student Research Internships Conference

Tetranychus urticae are a species of pests that are very problematic in agricultural environments, as they cause lots of damage to a wide variety of crops. One step in figuring out a solution to this problem is through the use of RNA interference. After synchronizing the spider mites, they are treated with the dsRNA solution. The dsRNA is cleavage inside the mite, and the siRNA fragments then bind to a target gene in hopes of homologous sequence recognition leading to knockout/deregulation of the target gene. After treatment, the mites are observed for multiple variables, primarily fecundity and survival. If a …

Dissolving Nature/Nurture: Development As Coupled Interaction, Derek E. Oswick

Electronic Thesis and Dissertation Repository

For many, the Nature/Nurture approach to development is a quaint figment of the past. We have moved on, one might think; everyone thinks that both categories are important for development, not merely one. The reality, however, is not so simple. In this dissertation, I argue that contemporary biology has not succeeded in getting out from under the shadow of Nature/Nurture, despite everyone being some sort of interactionist about development. The central aim of my project is to offer a form of developmental interactionism worth having, which succeeds in shedding the pernicious aspects of Nature/Nurture. I begin by giving an overview …

Identification Of Dna Methylation Episignatures For Classification And Phenotype/Genotype Correlation In Mendelian Neurodevelopmental Disorders, John Reilly

Electronic Thesis and Dissertation Repository

ABSTRACT: Diagnosis for neurodevelopmental disorders poses numerous challenges, related to the lack of specific findings and limited understanding of clinical impact of the majority of genetic variation. Epigenomics mechanisms involve chemical modifications in DNA that involve a range of cellular mechanisms. DNA methylation is an epigenetic mechanism involving addition and removal of methyl groups to cytosine residues. These methylation signals form episignatures; patterns of methylation that can be used as biomarkers capable of differentiating neurodevelopmental disorders. EpiSigns have enabled molecular diagnosis of a number of genetic conditions, classification of variants of unknown significance, and provided insights into the pathophysiology of …

Families' Healthcare Experiences For Children With Inherited Metabolic Diseases: Protocol For A Mixed Methods Cohort Study, Andrea J. Chow, Ryan Iverson, Monica Lamoureux, Kylie Tingley, Isabel Jordan, Nicole Pallone, Maureen Smith, Zobaida Al-Baldawi, Pranesh Chakraborty, Jamie Brehaut, Alicia Chan, Eyal Cohen, Sarah Dyack, Lisa Jane Gillis, Sharan Goobie, Ian D. Graham, Cheryl R. Greenberg, Jeremy M. Grimshaw, Robin Z. Hayeems, Shailly Jain-Ghai, Ann Jolly, Sara Khangura, Jennifer J. Mackenzie, Nathalie Major, John J. Mitchell, Stuart G. Nicholls

Paediatrics Publications

Introduction Children with inherited metabolic diseases (IMDs) often have complex and intensive healthcare needs and their families face challenges in receiving high-quality, family centred health services. Improvement in care requires complex interventions involving multiple components and stakeholders, customised to specific care contexts. This study aims to comprehensively understand the healthcare experiences of children with IMDs and their families across Canada. Methods and analysis A two-stage explanatory sequential mixed methods design will be used. Stage 1: quantitative data on healthcare networks and encounter experiences will be collected from 100 parent/guardians through a care map, 2 baseline questionnaires and 17 weekly diaries …

The Genetics Of Pain: An Exploration Of Gene-By-Environment Interactions And Their Effects On Pain, Mohamad F. Fakhereddin

Electronic Thesis and Dissertation Repository

The findings presented in this dissertation are part of the bigger SYMBIOME project which aims to use the biopsychosocial model of pain to develop a prognostic clinical phenotype for people that experience musculoskeletal (MSK) trauma. Chapter 2 presents an exploratory analysis to assess the relationships between genetic polymorphisms and pain severity and interference. Early childhood trauma was also explored as a moderator between genetic polymorphisms and pain outcomes. For pain severity, major allele carriers (A/A and G/A) of FKBP5 rs9394314 reported significantly higher scores than minor allele carriers (G/G). Further, major allele carriers who had at least one adverse childhood …

Applications Of Genetic Testing For Endocrine And Metabolic Disorders, Amanda Berberich

Electronic Thesis and Dissertation Repository

Knowledge of inherited diseases and the ability to rapidly, efficiently and comprehensively perform genetic testing are advancing steadily. However, the ideal approach to translate this ability into clinical applications for endocrine disorders has yet to be determined. This work focuses on aspects of clinically translating knowledge of select heritable endocrine and metabolic conditions.

For maturity onset diabetes of the young (MODY), a monogenic disorder with no current consensus guidelines governing testing procedures, this work addresses methods to improve detection by validating the use of next generation sequencing-based techniques to identify MODY cases and to detect copy number variations.

For very …

The Genetic Landscape Of Neurodegenerative And Cerebrovascular Disease Phenotypes., Allison A. Dilliott

Electronic Thesis and Dissertation Repository

Neurodegenerative diseases are progressive, incurable conditions characterized by neuronal degeneration and protein aggregation, resulting in cognitive decline and/or motor dysfunction. Over half a million Canadians are affected with these diseases, and the number of cases is expected to rise as the aging population grows and average lifespans continue to increase. There are currently no curative treatments, and only few therapeutics are available to target disease symptoms or slow disease progression. Further, diagnosis can be challenging, relying on clinical features that are often highly heterogeneous between patients. Gaining a greater understanding of the full spectrum of genetic factors contributing to these …

Genetic Approaches For The Study Of Complex Human Diseases, Julieta Lazarte

Electronic Thesis and Dissertation Repository

The field of human genetics has evolved from its initial narrow focus on single-gene Mendelian disorders, which largely affect children, to our current understanding that for most diseases there is continuum of rare to common variants which can exert a range of phenotypic effects. Despite advances in sequencing capabilities and our overall understanding of diseases, there remains a large proportion of heritability unexplained. Through the use of next-generation sequencing technologies and DNA microarray, I have explored a spectrum of genetic variations from rare, single and structural variants to common variants in individuals with i) “lone” atrial fibrillation; ii) familial hypercholesterolemia; …

Can A Lifestyle Genomics Intervention Motivate Patients To Engage In Greater Physical Activity Than A Population-Based Intervention? Results From The Now Randomized Controlled Trial, Justine R. Horne, Jason Gilliland, Tara Leckie, Colleen O'Connor, Jamie A. Seabrook, Janet Madill

Paediatrics Publications

Background: Lifestyle genomics (LGx) is a science that explores interactions between genetic variation, lifestyle components such as physical activity (PA), and subsequent health- and performance-related outcomes. The objective of this study was to determine whether an LGx intervention could motivate enhanced engagement in PA to a greater extent than a population-based intervention. Methods: In this pragmatic randomized controlled trial, participants received either the standard, population-based Group Lifestyle BalanceTM (GLB) program intervention or the GLB program in addition to the provision of LGx information and advice (GLB + LGx). Participants (n = 140) completed a 7-day PA recall at baseline, 3, …

Can A Lifestyle Genomics Intervention Motivate Patients To Engage In Greater Physical Activity Than A Population-Based Intervention? Results From The Now Randomized Controlled Trial, Justine R. Horne, Jason Gilliland, Tara Leckie, Colleen O'Connor, Jamie A. Seabrook, Janet Madill

Paediatrics Publications

Background: Lifestyle genomics (LGx) is a science that explores interactions between genetic variation, lifestyle components such as physical activity (PA), and subsequent health- and performance-related outcomes. The objective of this study was to determine whether an LGx intervention could motivate enhanced engagement in PA to a greater extent than a population-based intervention. Methods: In this pragmatic randomized controlled trial, participants received either the standard, population-based Group Lifestyle BalanceTM (GLB) program intervention or the GLB program in addition to the provision of LGx information and advice (GLB + LGx). Participants (n = 140) completed a 7-day PA recall at baseline, 3, …

Epigenetics A Decolonizing Science, Wade Paul

Electronic Thesis and Dissertation Repository

Epigenetics is the study of gene expression that does not entail alterations to the actual DNA. Decolonization is a theoretical and political movement that seeks to deconstruct colonial institutions and ideologies and reconstruct new and balanced approaches that accept and respect Indigenous worldviews. This project studies the decolonizing potential of epigenetics. Using genealogy as the method, the study establishes a long history of reductionist and deterministic thought that shaped the study of genetic science. Particular instances like thrift gene theory are explored to highlight how genetic explanations have been detrimental to the health and wellbeing of Indigenous people and illustrate …

Improved Fermentation Design And Screening Devices For Biobutanol Production, Garret Christopher Munch

Electronic Thesis and Dissertation Repository

A worldwide increase in demand for renewable fuels has revived interest in fermentatively produced butanol. However, butanol fermentation suffers from low product yields and productivity. The work presented in this thesis addresses part of these research and development needs at three levels: innovative fermentation process design; genetic manipulation for strain enhancement; and the development of a new tool for anaerobic process characterization and optimization.

Product yield could be increased through traditional fermentation engineering. Co-fermentation of butyric acid with glycerol increased the butanol yield from 0.45 mol/mol (mols C in butanol / mol C in substrates) to 0.51 mol/mol. In building …

Prevalence And Clinical Features Of Inflammatory Bowel Diseases Associated With Monogenic Variants, Identified By Whole-Exome Sequencing In 1000 Children At A Single Center, Eileen Crowley, Neil Warner, Jie Pan, Sam Khalouei, Abdul Elkadri, Karoline Fiedler, Justin Foong, Andrei L Turinsky, Dana Bronte-Tinkew, Shiqi Zhang

Paediatrics Publications

BACKGROUND & AIMS: A proportion of infants and young children with inflammatory bowel diseases (IBDs) have subtypes associated with a single gene variant (monogenic IBD). We aimed to determine the prevalence of monogenic disease in a cohort of pediatric patients with IBD.

METHODS: We performed whole-exome sequencing analyses of blood samples from an unselected cohort of 1005 children with IBD, aged 0-18 years (median age at diagnosis, 11.96 years) at a single center in Canada and their family members (2305 samples total). Variants believed to cause IBD were validated using Sanger sequencing. Biopsies from patients were analyzed by immunofluorescence and …

Advanced Phenotyping Of Otosclerosis In An Ontario Population And Two Large Newfoundland Families, Matthew B. Lucas

Electronic Thesis and Dissertation Repository

Otosclerosis is a relatively common hearing loss disorder characterized by abnormal bone growth in the otic capsule leading to stapes fixation. In approximately half of cases, otosclerosis is inherited as an autosomal dominant trait. Typically, gene discovery efforts rely on surgical confirmation, audiometry and occasionally acoustic reflexes to identify affected cases of otosclerosis within families, requiring that the otosclerosis was at an advanced stage to be detected. This makes it difficult to identify individuals with early otosclerosis. The use of advanced phenotyping to identify cases of otosclerosis was tested in an Ontario otosclerotic population as well as in two large …

The Now Trial: A Pragmatic Randomized Controlled Trial Of Personalized, Genetic-Based Lifestyle Advice, Justine Rochelle Horne

Electronic Thesis and Dissertation Repository

Background: The impact of nutrigenomics and lifestyle genomics interventions on health outcomes and behaviours remains controversial and under-explored.

Objectives: To determine the short-term (3-month), moderate-term (6-month) and long-term (12-month) impact of providing personalized, genetic-based lifestyle information and advice on anthropometric measures, as well as dietary intake and adherence.

Methods: The nutrigenomics, overweight/obesity and weight management trial (NOW Trial) is a pragmatic randomized controlled trial that was incorporated into the Group Lifestyle Balance™ (GLB) program (N=140). Inclusion criteria: overweight or obesity (BMI ≥ 25 kg/m²), ≥ 18 years of age, English-speaking, having access to internet at least …

Are Specific Learning Disorders Truly Specific, And Are They Disorders?, Lien Peters, Daniel Ansari

Brain and Mind Institute Researchers' Publications

© 2019 The Authors Specific learning disorders, such as dyslexia and dyscalculia, are frequently studied to inform our understanding of cognitive development, genetic mechanisms and brain function. In this Opinion Paper, we discuss limitations of this research approach, including the use of arbitrary criteria to select groups of children, heterogeneity within groups and overlap between domains of learning. By drawing on evidence from cognitive science, neuroscience and genetics, we propose an alternative, dimensional framework. We argue that we need to overcome the problems associated with a categorical approach by taking into account interacting factors at multiple levels of analysis that …

Functional Network Resilience To Pathology In Presymptomatic Genetic Frontotemporal Dementia, Timothy Rittman, Robin Borchert, Simon Jones, John Van Swieten, Barbara Borroni, Daniela Galimberti, Mario Masellis, Maria Carmela Tartaglia, Caroline Graff, Fabrizio Tagliavini, Giovanni B. Frisoni, Robert Laforce, Elizabeth Finger, Alexandre Mendonça, Sandro Sorbi, Jonathan D. Rohrer, James B. Rowe, Sónia Afonso, Maria Rosario Almeida, Sarah Anderl-Straub, Christin Andersson, Anna Antonell, Silvana Archetti, Andrea Arighi, Mircea Balasa, Myriam Barandiaran, Nuria Bargalló, Robart Bartha, Benjamin Bender, Luisa Benussi, Valentina Bessi, Giuliano Binetti

Medical Biophysics Publications

© 2019 The Authors The presymptomatic phase of neurodegenerative diseases are characterized by structural brain changes without significant clinical features. We set out to investigate the contribution of functional network resilience to preserved cognition in presymptomatic genetic frontotemporal dementia. We studied 172 people from families carrying genetic abnormalities in C9orf72, MAPT, or PGRN. Networks were extracted from functional MRI data and assessed using graph theoretical analysis. We found that despite loss of both brain volume and functional connections, there is maintenance of an efficient topological organization of the brain's functional network in the years leading up to the estimated age …

Development Of Criteria For Epilepsy Genetic Testing In Ontario, Canada, Puneet Jain, Danielle Andrade, Elizabeth Donner, David Dyment, Asuri N. Prasad, Sharan Goobie, Kym Boycott, Matthew Lines, O. Carter Snead

Paediatrics Publications

Multiple genes/variants have been implicated in various epileptic conditions. However, there is little general guidance available on the circumstances in which genetic testing is indicated and test selection in order to guide optimal test appropriateness and benefit. This is an account of the development of guidelines for genetic testing in epilepsy, which have been developed in Ontario, Canada. The Genetic Testing Advisory Committee was established in Ontario to review the clinical utility and validity of genetic tests and the provision of genetic testing in Ontario. As part of their mandate, the committee also developed recommendations and guidelines for genetic testing …

Study Protocol Of A Pragmatic Randomized Controlled Trial Incorporated Into The Group Lifestyle Balance™ Program: The Nutrigenomics, Overweight/Obesity And Weight Management Trial (The Now Trial), Justine Horne, Jason A. Gilliland, Colleen O’Connor,, Jamie A. Seabrook, Peter Hannaberg, Janet Madill

Human Environments Analysis Lab (HEAL)

Background

The nutrigenomics, overweight/obesity and weight management trial (NOW Trial) is a pragmatic randomized controlled trial of community-dwelling adults recruited from the Group Lifestyle Balance™ (GLB™) Program. The GLB™ Program (formerly referred to as the Diabetes Prevention Program) is an evidence-based, intensive weight management program, which was offered to overweight/obese patients (BMI ≥ 25.0 kg/m2) in a rural Ontario community.

Methods

Patients enrolled in the GLB™ Program were invited to participate in this study. GLB™ groups were randomized 1:1 to receive either the standard GLB™ program + population-based lifestyle advice for weight management, or a modified GLB™ program + personalized, …

The Clinical Impact Of Copy Number Variants In Inherited Bone Marrow Failure Syndromes, Nicolas Waespe, Santhosh Dhanraj, Manju Wahala, Elena Tsangaris, Tom Enbar, Bozana Zlateska, Hongbing Li, Robert J Klaassen, Conrad V Fernandez, Geoff D E Cuvelier, John K Wu, Yves D Pastore, Mariana Silva, Jeffrey H Lipton, Joseé Brossard, Bruno Michon, Sharon Abish, Macgregor Steele, Roona Sinha, Mark J Belletrutti, Vicky R Breakey, Lawrence Jardine, Lisa Goodyear, Liat Kofler, Michaela Cada, Lillian Sung, Mary Shago, Stephen W Scherer, Yigal Dror

Paediatrics Publications

Inherited bone marrow failure syndromes (IBMFSs) comprise a genetically heterogeneous group of diseases with hematopoietic failure and a wide array of physical malformations. Copy number variants (CNVs) were reported in some IBMFSs. It is unclear what impact CNVs play in patients evaluated for a suspected diagnosis of IBMFS. Clinical and genetic data of 323 patients from the Canadian Inherited Marrow Failure Registry from 2001 to 2014, who had a documented genetic work-up, were analyzed. Cases with pathogenic CNVs (at least 1 kilobasepairs) were compared to cases with other mutations. Genotype-phenotype correlations were performed to assess the impact of CNVs. Pathogenic …

Gene Discovery In Mendelian And Complex Diseases, Sali Farhan

Electronic Thesis and Dissertation Repository

Through the Finding of Rare Disease Genes in Canada (FORGE Canada) initiative, individuals affected with rare Mendelian diseases were clinically ascertained with a goal of identifying the genetic origin of their disease. Herein, I describe the methods for identifying the genetic basis of four Mendelian diseases. The application of next generation sequencing led to the discovery of non-synonymous variation in the DNA of individuals affected by rare diseases. The effects of the candidate variants were assessed using a series of functional experiments to complement the human genetics data. The variants observed in patients’ cells are extremely rare, were consistently predicted …

Alagille Syndrome: Clinical Perspectives, Maha Saleh, Binita M. Kamath, David Chitayat

Paediatrics Publications

Alagille syndrome is an autosomal dominant, complex multisystem disorder characterized by the presence of three out of five major clinical criteria: cholestasis with bile duct paucity on liver biopsy, congenital cardiac defects (with particular involvement of the pulmonary arteries), posterior embryotoxon in the eye, characteristic facial features, and butterfly vertebrae. Renal and vascular abnormalities can also occur. Inter- and intrafamilial variabilities in the clinical manifestations are common. We reviewed the clinical features and management as well as the molecular basis of Alagille syndrome.

Association Between Mapt Haplotype And Memory Function In Patients With Parkinson's Disease And Healthy Aging Individuals, Sophie E. Winder-Rhodes, Adam Hampshire, James B. Rowe, Jonathan E. Peelle, Trevor W. Robbins, Adrian M. Owen, Roger A. Barker

Brain and Mind Institute Researchers' Publications

Genetic variation is associated with differences in the function of the brain as well as its susceptibility to disease. The common H1 haplotypic variant of the microtubule-associated protein tau gene (MAPT) has been related to an increased risk for Parkinson's disease (PD). Furthermore, among PD patients, H1 homozygotes have an accelerated progression to dementia. We investigated the neurocognitive correlates of MAPT haplotypes using functional magnetic resonance imaging. Thirty-seven nondemented patients with PD (19 H1/H1, 18 H2 carriers) and 40 age-matched controls (21 H1/H1, 19 H2 carriers) were scanned during performance of a picture memory encoding task. Behaviorally, H1 homozygosity was …

Divergent Transcriptional Responses To Low Temperature Among Populations Of Alpine And Lowland Species Of New Zealand Stick Insects (Micrarchus)., Luke T Dunning, Alice B Dennis, Brent J Sinclair, Richard D Newcomb, Thomas R Buckley

Biology Publications

In widespread and genetically structured populations, temperature variation may lead to among-population differentiation of thermal biology. The New Zealand stick insect genus Micrarchus contains four species that inhabit different thermal environments, two of which are geographically widespread. RNA-Seq and quantitative PCR were used to investigate the transcriptional responses to cold shock among lowland and alpine species to identify cold-responsive transcripts that differ between the species and to determine whether there is intraspecific geographical variation in gene expression. We also used mitochondrial DNA, nuclear 28S ribosomal DNA and transcriptome-wide SNPs to determine phylogeographic structure and the potential for differences in genetic …

Insights Into The Function Of The Fatc Domain Of Saccharomyces Cervisiae Tra1 Via Mutation And Suppressor Analysis, Samantha A. Pillon

Electronic Thesis and Dissertation Repository

The regulation of transcription is an important cellular function because it is the first step in gene regulation. In Saccharomyces cerevisiae, two protein complexes, SAGA and NuA4, act as regulators of transcription. A common protein shared between these two complexes, called Tra1, regulates transcriptional activation through its interaction with gene specific transcriptional activators. Tra1 is a member of the PIKK family of proteins, which are characterized by FAT, PI3K and FATC domains. The FATC domain encompasses the terminal 33-35 residues of the protein. Two mutations within the FATC domain, tra1-L3733A and tra1-F3744A, result in slow growth under stress …

Language In Genetics Research Informed Consent: The Language Gap And Unrecognized Miscommunication, Justin Morgenstern

Electronic Thesis and Dissertation Repository

Informed choice is fundamentally a process of communication, reliant entirely on the tools of language. However, the meanings and understandings of words change with time, setting, and context, threatening the basis of consent. We conducted a qualitative content analysis of Canadian genetics research documents, exploring the impacts of language on informed consent. Numerous language usages were noted as potential barriers to informed consent, including language that was vague, variable, and unusually defined. Unique combinations of words were observed to generate novel concepts without clear meanings and definitions were absent or unclear. However, the ambiguity of the language was concealed by …