1. Department of Twin Research & Genetic Epidemiology, King’s College London, London, United Kingdom
2. University Medical Center Groningen, Department of Genetics, University of Groningen, Groningen, Netherlands
3. Department of Mathematics, Imperial College London, London, United Kingdom
4. Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, Neuherberg, Germany
5. University Medical Center Groningen, Department of Pediatrics, University of Groningen, Groningen, Netherlands
6. K.G. Jebsen Coeliac Disease Research Centre, Department of Immunology, University of Oslo, Oslo, Norway