1. Red Cell Pathology Unit; Hospital Clínic, IDIBAPS, University of Barcelona; Spain
2. Immunology Department; Hospital Clínic, IDIBAPS; Barcelona Spain
3. Department of Clinical Chemistry and Haematology; University Medical Center Utrecht; Utrecht the Netherlands
4. Department of Pediatrics; Hospital Niño Jesús; Madrid Spain
5. Department of Medical Genetics; University Medical Center Utrecht; Utrecht the Netherlands