Article Text
Abstract
Objective Haemorrhoidal disease (HEM) affects a large and silently suffering fraction of the population but its aetiology, including suspected genetic predisposition, is poorly understood. We report the first genome-wide association study (GWAS) meta-analysis to identify genetic risk factors for HEM to date.
Design We conducted a GWAS meta-analysis of 218 920 patients with HEM and 725 213 controls of European ancestry. Using GWAS summary statistics, we performed multiple genetic correlation analyses between HEM and other traits as well as calculated HEM polygenic risk scores (PRS) and evaluated their translational potential in independent datasets. Using functional annotation of GWAS results, we identified HEM candidate genes, which differential expression and coexpression in HEM tissues were evaluated employing RNA-seq analyses. The localisation of expressed proteins at selected loci was investigated by immunohistochemistry.
Results We demonstrate modest heritability and genetic correlation of HEM with several other diseases from the GI, neuroaffective and cardiovascular domains. HEM PRS validated in 180 435 individuals from independent datasets allowed the identification of those at risk and correlated with younger age of onset and recurrent surgery. We identified 102 independent HEM risk loci harbouring genes whose expression is enriched in blood vessels and GI tissues, and in pathways associated with smooth muscles, epithelial and endothelial development and morphogenesis. Network transcriptomic analyses highlighted HEM gene coexpression modules that are relevant to the development and integrity of the musculoskeletal and epidermal systems, and the organisation of the extracellular matrix.
Conclusion HEM has a genetic component that predisposes to smooth muscle, epithelial and connective tissue dysfunction.
- anorectal disorders
- genetics
- anal canal histopathology
Data availability statement
Data are available in a public, open access repository. Genome-wide summary statistics of our analyses are publicly available through our web browser (http://hemorrhoids.online) and have been submitted to the European Bioinformatics Institute (www.ebi.ac.uk/gwas) under the accession number GCST90014033. RNA-seq data have been deposited at NCBI Gene Expression Omnibus (GEO) under the accession number GSE154650.
This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See: https://creativecommons.org/licenses/by/4.0/.
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Data availability statement
Data are available in a public, open access repository. Genome-wide summary statistics of our analyses are publicly available through our web browser (http://hemorrhoids.online) and have been submitted to the European Bioinformatics Institute (www.ebi.ac.uk/gwas) under the accession number GCST90014033. RNA-seq data have been deposited at NCBI Gene Expression Omnibus (GEO) under the accession number GSE154650.
Supplementary materials
Supplementary Data
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Footnotes
Twitter @mruehlemann, @beyderlab, @damato_mauro
TZ, DE and SJ contributed equally.
CS, MD and AF contributed equally.
Contributors AF, CS and MD’A were responsible for the concept and the design of the study. CS and GB coordinated the recruitment of the German clinical cohort. VK, JG, IV, BS, HGP, AH, JJ, JW, TB, MD, FB, SH, JK, JS, WK, MZo, CGN, TL, JT and WS recruited and phenotyped patients of the clinical cohorts. VK collected and phenotyped the biopsy samples that were used in the immunohistochemistry and transcriptome analyses. Animal samples for histology were taken and provided by KP, SZ, LF, TG, FHL and KM-R. Immunohistochemistry and histology analyses were performed by FC and TW with support of JW and CR. TZ, DE and FD performed genotype and phenotype data collection. TZ, DE, and FD performed GWAS data quality control and imputation. SJ performed the transcriptome (RNA-Seq) analysis with help from GI and PR. FU-W, SBu, and MF helped with bioinformatic analyses. IFJ, KB, SBr, CLR, CE, OBP, and HU conducted analyses in DBDS and DNPR. HC, VL, RJ, NF, WL, ML, and UN-G contributed German control data. SBu, CD, HV, AG and JH contributed the GWAS data on diverticular disease. Norwegian HUNT data were contributed by AHS, THK, MEG, LT, EN-J and KH. The Estonian dataset was provided by TE and MT-L. Protein models and analyses were performed by GM. The analysis of the MGI data set was performed by MZa, BV, AP and LGF. The 23andMe data set was analyzed and provided by OS, ESN, and VV. MW implemented ABO blood-group inference. SC, PRS, GF and AB performed site-directed ANO1 mutagenesis and whole-cell electrophysiology experiments. TZ, DE implemented statistical models and performed the (meta-)analysis. TZ, DE, and SJ curated and interpreted results. MS designed online supplementary figure S2 with scientific input from NM and AF. The GWAS data browser was implemented by MR and set up by GH-S. AF, MD’A and DE wrote the manuscript draft with substantial contributions from TZ and SJ. All authors reviewed, edited and approved the final manuscript.
Funding This project was funded by Andre Franke’s and Clemens Schafmayer’s DFG grant “Discovery of risk factors for hemorrhoids“ (ID: FR 2821/19-1). The study received infrastructure support from the DFG Cluster of Excellence 2167 “Precision Medicine in Chronic Inflammation (PMI)” (DFG Grant: “EXC2167”). The project was supported by grants from the Swedish Research Council to MD (VR 2017-02403), the Novo Nordisk Foundation (grants NNF17OC0027594 and NNF14CC0001) and BigTempHealth (grant 5153-00002B). We are indebted to the valuable assistance by Tanja Wesse (Genotyping of the German samples) and Petra Röthgen (German DZHK control data set). We thank Clemens Franke (Institute of Anatomy, Christian-Albrechts-University of Kiel, Kiel, Germany) for graphic assistance (figure 6, online supplementary figure S1 and S13). This research has been conducted using the UK Biobank Resource under Application Number 31435. The work on cross-trait analysis for diverticular disease presented in this manuscript was supported by the German Research Council (DFG, ID: Ha3091/9-1) and the Austrian Science Fund (FWF, ID: I1542-B13). Data access to the UK biobank data for diverticular disease was granted under project numbers 22691. EGCUT work has also been supported by the European Regional Development Fund and grants SP1GI18045T, No. 2014-2020.4.01.15-0012 GENTRANSMED and 2014-2020.4.01.16-0125 This study was also funded by EU H2020 grant 692145, Estonian Research Council Grant PUT1660. Data analyzes with Estonian datasets were carried out in part in the High-Performance Computing Center of University of Tartu. The work on site-directed mutagenesis of ANO1 and whole-cell electrophysiology was funded by NIH DK057061. We would like to thank the research participants and employees of 23andMe for making this work possible. The following members of the 23andMe Research Team contributed to this study: Michelle Agee, Adam Auton, Robert K. Bell, Katarzyna Bryc, Sarah L. Elson, Pierre Fontanillas, Nicholas A. Furlotte, David A. Hinds, Karen E. Huber, Aaron Kleinman, Nadia K. Litterman, Jennifer C. McCreight, Matthew H. McIntyre, Joanna L. Mountain, Elizabeth S. Noblin, Carrie A.M. Northover, Steven J. Pitts, J. Fah Sathirapongsasuti, Olga V. Sazonova, Janie F. Shelton, Suyash Shringarpure, Chao Tian, Joyce Y. Tung, and Vladimir Vacic.
Competing interests Vladimir Vacic and Olga V. Sazonova are/were employed by and hold stock or stock options in 23andMe, Inc. All other authors have nothing to declare.
Provenance and peer review Not commissioned; externally peer reviewed.
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