1. Center for Hemochromatosis, Department of Internal Medicine, University Hospital Policlinico di Modena, Modena, Italy.
2. Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA.
3. Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
4. Howard Hughes Medical Institute, Departments of Biological Chemistry and Internal Medicine, University of Michigan Medical Center, Ann Arbor, MI 48109–0650, USA.