About the Authors

Ana M. Valdes

ana.valdes@kcl.ac.uk

Affiliation Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom

Unnur Styrkarsdottir

Affiliation deCODE Genetics, Reykjavik, Iceland

Michael Doherty

Affiliation Academic Rheumatology, University of Nottingham, Nottingham, United Kingdom

David L. Morris

Affiliation Divisions of Genetics and Molecular Medicine and Immunology, Infection and Inflammatory Diseases, King's College London, London, United Kingdom

Massimo Mangino

Affiliation Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom

Agu Tamm

Affiliation Department of Internal Medicine, University of Tartu, Tartu, Estonia

Sally A. Doherty

Affiliation Academic Rheumatology, University of Nottingham, Nottingham, United Kingdom

Kalle Kisand

Affiliation Department of Internal Medicine, University of Tartu, Tartu, Estonia

Irina Kerna

Affiliation Department of Internal Medicine, University of Tartu, Tartu, Estonia

Ann Tamm

Affiliations Department of Internal Medicine, University of Tartu, Tartu, Estonia, Department of Sports Medicine and Rehabilitation, University of Tartu, Tartu, Estonia

Margaret Wheeler

Affiliation Academic Rheumatology, University of Nottingham, Nottingham, United Kingdom

Rose A. Maciewicz

Affiliation Respiratory & Inflammation Research Area, AstraZeneca, Loughborough, United Kingdom

Weiya Zhang

Affiliation Academic Rheumatology, University of Nottingham, Nottingham, United Kingdom

Kenneth R. Muir

Affiliation Health Sciences Research Institute, Warwick Medical School University of Warwick, Coventry, United Kingdom

Elaine M. Dennison

Affiliation Medical Research Council Lifecourse Epidemiology Unit University of Southampton Southampton, United Kingdom

Deborah J. Hart

Affiliation Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom

Sarah Metrustry

Affiliation Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom

Ingileif Jonsdottir

Affiliations deCODE Genetics, Reykjavik, Iceland, Faculty of Medicine, University of Iceland, Reykjavik, Iceland

Gudbjorn F. Jonsson

Affiliation deCODE Genetics, Reykjavik, Iceland

Helgi Jonsson

Affiliations Faculty of Medicine, University of Iceland, Reykjavik, Iceland, Department of Medicine, Landspitali University Hospital, Reykjavik, Iceland

Thorvaldur Ingvarsson

Affiliations Faculty of Medicine, University of Iceland, Reykjavik, Iceland, University Hospital, Institution of Health Science, University of Akureyri, Akureyri, Iceland

Cyrus Cooper

Affiliations Medical Research Council Lifecourse Epidemiology Unit University of Southampton Southampton, United Kingdom, Musculoskeletal Biomedical Research Unit, University of Oxford, Oxford, United Kingdom

Timothy J. Vyse

Affiliation Divisions of Genetics and Molecular Medicine and Immunology, Infection and Inflammatory Diseases, King's College London, London, United Kingdom

Tim D. Spector

Affiliation Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom

Kari Stefansson

Contributed equally to this work with: Kari Stefansson, Nigel K. Arden

Affiliations deCODE Genetics, Reykjavik, Iceland, Faculty of Medicine, University of Iceland, Reykjavik, Iceland

Nigel K. Arden

Contributed equally to this work with: Kari Stefansson, Nigel K. Arden

Affiliations Medical Research Council Lifecourse Epidemiology Unit University of Southampton Southampton, United Kingdom, Musculoskeletal Biomedical Research Unit, University of Oxford, Oxford, United Kingdom

Competing Interests

Dr. RA Maciewicz is employed by, owns stock and has patent applications for AstraZeneca. U. Styrkarsdottir, I. Jonsdottir, G. Jonsson and K. Stefansson are employed by deCODE Genetics. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials..

Author Contributions

Conceived and designed the experiments: AMV US MD DLM TDS KS NKA. Performed the experiments: SAD MW US KK IK AT SM. Analyzed the data: AMV US DLM MM. Contributed reagents/materials/analysis tools: MD AT RAM WZ KRM EMD DJH IJ GFJ HJ TI CC TJV TDS KS NKA. Wrote the paper: AMV US.