1 Department of Pediatrics, and Adolescent Medicine, Faculty of Medicine and University Hospital of Cologne, University of Cologne, Cologne, Germany. ruth.janoschek@uk-koeln.de.
2 Department of Pediatrics, and Adolescent Medicine, Faculty of Medicine and University Hospital of Cologne, University of Cologne, Cologne, Germany. thorben.hoffmann@uk-koeln.de.
3 Department of Pediatrics, and Adolescent Medicine, Faculty of Medicine and University Hospital of Cologne, University of Cologne, Cologne, Germany.
4 Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.
5 Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
6 Cologne Center for Musculoskeletal Biomechanics (CCMB), Cologne, Germany.