1. Osteoarticular Research Group, Institute of Pathology, University of Bern, Bern, Switzerland.
2. Present address of Shawn Patrick Grogan is The Division of Arthritis Research, The Scripps Research Institute, La Jolla, California.
3. Research Division of the Department of Surgery, University of Basel, Basel, Switzerland.
4. Zimmer Orthopedics, Winterthur, Switzerland.
5. Cartilage and Connective Tissue Research, Mayo Clinic College of Medicine, Rochester, Minnesota.