Using Genetic Methods to Get Insight Into Human Complex Traits

Total Page:16

File Type:pdf, Size:1020Kb

Using Genetic Methods to Get Insight Into Human Complex Traits Using genetic methods to get insight into human complex traits Bochao Danae Lin READING COMMITTEE: Prof. CV Dolan, Vrije Universiteit Amsterdam Prof. NG Martin, QIMR Berghofer Medical Research Institute, Brisbane, Australia Prof. H Snieder, Universitair Medisch Centrum Groningen Prof. M Kayser, Erasmus Universiteit Medisch Centrum Rotterdam Dr. DJA Smit, Academisch Medisch Centrum Amsterdam Dr. R Menezes, Vrije Universiteit Medisch Centrum Amsterdam PARANYMPHS: Jenny van Dongen Junfeng Wang ACKNOWLEDGEMENTS: I would like to acknowledge the financial support I received from the China Scholarship Council (201206180099) for my study. I also acknowledge the financial support from the Faculty of Behavioural and Movement Sciences to visit Notre Dame University, United States. The data collection in the Netherlands Twin Register was supported by multiple grants from the Netherlands Organization for Scientific Research and Development Grant (ZonMW); the Biobanking and Biomolecular Resources Research Infrastructure (BBMRI‐NL) [184.021.007]; the European Research Council, Genetics of Mental Illness [ERC‐230374]; the National Institute for Mental Health (NIMH) [1RC2 MH089951‐01: Integration of Genomics & Transcriptomics in Normal Twins & Major Depression, and 1RC2MH089995‐01: Genomics of Developmental Trajectories in Twins]; and the Avera Institute for Human Genetics , Sioux Falls (USA). I very warmly thank all twins and their family members for taking part in the research projects of the Netherlands Twin Register. ISBN: 978‐94‐6295‐615‐5 Cover design and Layout: Saymand Alerachi Printed by: Proefschriftmaken VRIJE UNIVERSITEIT Using genetic methods to get insight into human complex traits ACADEMISCH PROEFSCHRIFT ter verkrijging van de graad Doctor aan de Vrije Universiteit Amsterdam, op gezag van de rector magnificus prof.dr. V. Subramaniam, in het openbaar te verdedigen ten overstaan van de promotiecommissie van de Faculteit der Gedrags- en Bewegingswetenschappen op donderdag 20 april 2017 om 11.45 uur in het auditorium van de universiteit, De Boelelaan 1105 door Bochao Lin geboren te Jilin, China promotor: prof.dr. D.I. Boomsma copromotoren: dr. J.J. Hottenga dr. A.H.M. Willemsen Table of Contents Chapter 1 General Introduction ........................................................................... 1 Part I: Visible traits .................................................................................................. 15 Chapter 2 Heritability and Genome‐Wide Association studies for hair color in a Dutch twin family based sample ........................................................................ 17 Appendix I. Details on methodology .................................................................. 34 Chapter 3 The genetic overlap between hair and eye color .............................. 45 Appendix II. GWAS results for eye color ............................................................. 51 Part II: Hematological profiles ................................................................................ 55 Chapter 4 Causes of variation in the neutrophil– lymphocyte and platelet‐ lymphocyte ratios: a twin‐family study .............................................................. 57 Appendix III. Age and BMI interaction effects on NLR and PLR .......................... 73 Appendix IV. Results for NLR and PLR in the total and unhealthy population ... 75 Chapter 5 SNP heritability and effects of genetic variants for neutrophil‐to‐ lymphocyte and platelet‐to‐lymphocyte ratio ................................................... 83 Appendix V. Details on eQTL analysis ............................................................... 107 Chapter 6 Heritability and GWA studies for the monocyte‐lymphocyte ratio . 111 Chapter 7 The interactive effects of age, sex, and lifestyle on the hematological profile. ............................................................................................................... 131 Part III: Epigenome‐wide studies .......................................................................... 145 Chapter 8 Blood hypomethylation is associated with elevated myeloid‐lymphoid ratios in cell‐specific active genomic regions ................................................... 147 Chapter 9 Epigenome‐wide association study for platelet‐lymphocyte ratio (PLR) level ................................................................................................................... 161 Chapter 10 General Summary and Discussion ................................................. 169 Bibliography .......................................................................................................... 182 Chapter 1 General Introduction We are all unique, even if we share certain characteristics with our family members and those around us. The individual differences that can be observed in the population are caused by a combination of genetic and environmental factors. In this PhD thesis I endeavor to add to our understanding of the way genetic factors explain individual differences in human complex traits by applying a variety of methodological tools to different sets of personal characteristics, which in genetics are commonly referred to as ‘phenotypes’. In this first chapter I provide a general background, describe the methods I applied to answer the questions about the etiology of individual differences, and I introduce the traits of interest, in which variation is analyzed in this thesis. 1.1 General background. Genetic studies of human complex traits aim to clarify the contribution of genetic factors to variation in the trait. The phrase ‘complex trait’ or ‘complex phenotype’ refers to traits, which result from variation at multiple genomic sites, and across multiple environmental factors. Complex traits do not follow a Mendelian pattern of inheritance and often show a continuous distribution in the population, either on the scale of measurement or on the underlying liability scale. Family studies, in particular twin studies, have proven to be useful tools to determine to which extent genetic factors influence individual variation in a traits, or stated differently, to provide us with estimates for the heritability of a trait [1]. Such studies, however, do not identify the source of the genetic contribution to individual differences, namely the variation in DNA sequence in human genomes. Until recently, there were two main approaches to gain information on the genetic variants influencing phenotypes of interest: candidate gene association studies and linkage studies. In a candidate gene association study the focus is on associations between the variation in the phenotype and variation in one or a few preselected genes. For example, my first genetic study conducted as part of my Master program investigated the association between rs16970495 (an intro variant on RASGRF1) and myopia in a sample of 557 Chinese adults. In this study I found that the A allele of rs16970495 was associated with an increased risk of myopia (OR=1.21, P=.003). However, such candidate gene studies are generally based on limited prior knowledge, especially in psychology or psychiatry, and often prove difficult to replicate in follow up studies [2]. Linkage studies do not focus on a specific gene but use data from family members to map individual differences in a trait to variation in genetic markers of a known chromosomal location. A location that correlates with the 1 quantitative trait of interest is referred to as a quantitative trait locus (QTL), and is more likely to contain a causal genetic variant. However, linkage studies require family data, such as big pedigrees, or large samples of sibling pairs and have a low resolution mapping, with resulting QTLs thus referring to broad chromosomal regions, rather than to a specific base pair position. In addition, linkage studies are well suited for Mendelian traits with high penetrance but less so for complex traits [3]. Fortunately, advances in genotyping technology have now made it both time‐ and cost‐ wise possible to explore a large part of the variation in the human genome. Assessment of genomic variation in DNA can be done by typing samples on SNP (single nucleotide polymorphisms) arrays, or by sequencing the complete genome, which provides additional information of genetic variants such as insertions and deletions (indels) and copy number variants (CNV). These developments have further been supported by advances in computational support and methodologies for high‐throughput data analysis. Imputation of missing genotypes in subjects with SNP array data, using a large reference panel of sequenced individuals such as the 1000 Genomes project [4], provides the possibilities for GWA studies to identify complex trait loci. The combination of arrays and sequence information results in a nearly complete number of studied genetic markers across the genome to map associations. Furthermore it allows to harmonize and combine datasets or results across research groups for meta‐analysis [5]. As a result, the last decade has seen a large number of identified genes, and more scientific achievements obtained by genome‐wide association studies (GWAS) for human complex traits. The results obtained by GWAS studies have provided the input for new analyses techniques, furthering our understanding of the way genetic influences are involved in individual variation, done by exploring the degree to which genes cluster in pathways, influence multiple traits or are differently expressed during the lifespan.
Recommended publications
  • Document Title: the Determination of the Physical Characteristics of an Individual from Biological Stains Author: Jack Ballantyne, Ph.D
    The author(s) shown below used Federal funds provided by the U.S. Department of Justice and prepared the following final report: Document Title: The Determination Of The Physical Characteristics Of An Individual From Biological Stains Author: Jack Ballantyne, Ph.D. Document No.: 223978 Date Received: September 2008 Award Number: 2005-MU-BX-K075 This report has not been published by the U.S. Department of Justice. To provide better customer service, NCJRS has made this Federally- funded grant final report available electronically in addition to traditional paper copies. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. THE DETERMINATION OF THE PHYSICAL CHARACTERISTICS OF AN INDIVIDUAL FROM BIOLOGICAL STAINS FINAL REPORT January 16 2007 Department of Justice, National Institute of Justcie Award Number: 2005-MU-BX-K075 (1 September 2005- 31 December 2007) Principal Investigator: Jack Ballantyne, Ph.D. Associate Professor Department of Chemistry Associate Director for Research National Center for Forensic Science 4000 Central Boulevard, Bldg#5 University of Central Florida Orlando, FL 32816-2366 Phone: (407) 823 4440 Fax: (407) 823 2252 e-mail: [email protected] This document is a research report submitted to the U.S. Department of Justice. This report has not been published by the Department. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. EXECUTIVE SUMMARY 1. It is now a matter of routine for the forensic scientist to obtain the genetic profile of an individual from DNA recovered from a biological stain deposited at a crime scene.
    [Show full text]
  • Functional Annotation of the Transcriptome of the Pig, Sus Scrofa, Based Upon Network Analysis of an Rnaseq Transcriptional Atlas
    Edinburgh Research Explorer Functional annotation of the transcriptome of the pig, Sus scrofa, based upon network analysis of an RNAseq transcriptional atlas Citation for published version: Summers, K, Bush, S, Wu, C, Su, A, Muriuki, C, Clark, E, Finlayson, H, Eory, L, Waddell, L, Talbot, R, Archibald, A & Hume, D 2020, 'Functional annotation of the transcriptome of the pig, Sus scrofa, based upon network analysis of an RNAseq transcriptional atlas', Frontiers in genetics. https://doi.org/10.3389/fgene.2019.01355 Digital Object Identifier (DOI): 10.3389/fgene.2019.01355 Link: Link to publication record in Edinburgh Research Explorer Document Version: Publisher's PDF, also known as Version of record Published In: Frontiers in genetics General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 01. Oct. 2021 ORIGINAL RESEARCH published: 14 February 2020 doi: 10.3389/fgene.2019.01355 Functional Annotation of the Transcriptome of the Pig, Sus scrofa, Based Upon Network Analysis of an RNAseq Transcriptional Atlas Kim M. Summers 1*†, Stephen J. Bush 2†, Chunlei Wu 3, Andrew I.
    [Show full text]
  • The Genome-Wide Impact of Trisomy 21 on DNA Methylation and Its Implications for Hematopoiesis
    ARTICLE https://doi.org/10.1038/s41467-021-21064-z OPEN The genome-wide impact of trisomy 21 on DNA methylation and its implications for hematopoiesis Ivo S. Muskens1,2, Shaobo Li 1,2,13, Thomas Jackson3,13, Natalina Elliot3,13, Helen M. Hansen4, Swe Swe Myint1,2, Priyatama Pandey1,2, Jeremy M. Schraw5,6, Ritu Roy7, Joaquin Anguiano4, Katerina Goudevenou3, Kimberly D. Siegmund 8, Philip J. Lupo5,6, Marella F. T. R. de Bruijn 9, Kyle M. Walsh 10,11, Paresh Vyas 9, Xiaomei Ma12, Anindita Roy 3, Irene Roberts3, Joseph L. Wiemels1,2 & ✉ Adam J. de Smith 1,2 1234567890():,; Down syndrome is associated with genome-wide perturbation of gene expression, which may be mediated by epigenetic changes. We perform an epigenome-wide association study on neonatal bloodspots comparing 196 newborns with Down syndrome and 439 newborns without Down syndrome, adjusting for cell-type heterogeneity, which identifies 652 epigenome-wide significant CpGs (P < 7.67 × 10−8) and 1,052 differentially methylated regions. Differential methylation at promoter/enhancer regions correlates with gene expression changes in Down syndrome versus non-Down syndrome fetal liver hematopoietic stem/progenitor cells (P < 0.0001). The top two differentially methylated regions overlap RUNX1 and FLI1, both important regulators of megakaryopoiesis and hematopoietic devel- opment, with significant hypermethylation at promoter regions of these two genes. Excluding Down syndrome newborns harboring preleukemic GATA1 mutations (N = 30), identified by targeted sequencing, has minimal impact on the epigenome-wide association study results. Down syndrome has profound, genome-wide effects on DNA methylation in hematopoietic cells in early life, which may contribute to the high frequency of hematological problems, including leukemia, in children with Down syndrome.
    [Show full text]
  • Identification of Genes Potentially Involved in Bone Metastasis by Genome-Wide Gene Expression Profile Analysis of Non-Small Cell Lung Cancer in Mice
    INTERNATIONAL JOURNAL OF ONCOLOGY 40: 1455-1469, 2012 Identification of genes potentially involved in bone metastasis by genome-wide gene expression profile analysis of non-small cell lung cancer in mice LE TAN DAT1,2, TAISUKE MATSUO1, TETSURO YOSHIMARU1, SOJI KAKIUCHI2, HISATSUGU GOTO2, MASAKI HANIBUCHI2, TAKUYA KURAMOTO1, YASUHIKO NISHIOKA2, SABURO SONE2 and TOYOMASA KATAGIRI1 1Division of Genome Medicine, Institute for Genome Research, The University of Tokushima; 2Department of Respiratory Medicine and Rheumatology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503, Japan Received October 26, 2011; Accepted December 22, 2011 DOI: 10.3892/ijo.2012.1348 Abstract. Lung cancer is commonly associated with multi- of this disease is predominantly due to the difficulty of early organ metastasis, and the bone is a frequent metastatic site diagnosis and the highly metastatic potential of lung cancer. In for lung cancer. However, the molecular mechanism of organ- many cases, metastases to multiple organs have already devel- specific metastasis remains poorly understood. To elucidate this oped by the time of diagnosis (2-4). In particular, ~30-40% of issue, we analyzed in this study genome-wide gene expression patients with advanced lung cancer will develop bone metas- profiles of 15 metastatic lesions from three organs (bone, lung tases in the course of their disease, resulting in a significant and liver) in a mouse model with multi-organ metastasis prop- negative impact on both morbidity and survival (3-5). Currently erties of human non-small cell lung cancer cells (ACC-LC319/ no curative therapy exists for bone metastasis, and clinical bone2), using a combination of laser-microbeam microdissec- management is generally palliative (3,6,7).
    [Show full text]