1. Department of Genetics, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Sorbonne Université, Paris, France;
2. INSERM UMR1170 and
3. University Paris-Saclay, Gustave Roussy, Villejuif, France;
4. Laboratory of Hematology, Robert Debré Hospital, AP-HP, Paris, France;
5. CNRS UMR7590, Sorbonne Universités, Université Pierre et Marie Curie-Paris 6-MNHN-IRD-IUC, Paris, France;
6. Department of Hematology, Centre Hospitalier Universitaire (CHU), Faculté de Médecine, University of Normandie Caen, Caen, France;
7. Department of Pediatric Hematology and Immunology, Robert Debré Hospital, AP-HP, Paris, France;
8. Department of Pediatric Hematology, Immunology and Oncology, CHU, Angers, France;
9. Department of Pediatrics, CHU La Réunion, Groupe Hospitalier Sud Réunion, France;
10. CNRS UMR9196, Gustave Roussy, Villejuif, France;
11. French Registry of Chronic Neutropenia, Trousseau Hospital, Paris, France;
12. Unit of Pediatric Hematology, Centre d’Investigation Clinique 1401 INSERM Centre d'Investigation Clinique Plurithématique, CHU Bordeaux, France;
13. Department of Pediatric Hematology, Timone Hospital, Assistance Publique-Hôpitaux de Marseille, Marseille, France;
14. Centre Hospitalier Côte Basque, Bayonne, France;
15. Department of Pediatrics, Centre Hospitalier Argenteuil, Argenteuil, France;
16. Child Neurology and Metabolic Disorders Department, Robert Debré Hospital, AP-HP, Paris, France;
17. Department of Pediatric Hematology and Oncology, CHU, Saint-Etienne, France;
18. Institut of Pediatric Hematology and Oncology, Lyon, France;
19. Department of Pediatric Hematology and Oncology, CHU, Brest, France;
20. Department of Clinical Immunology, Saint-Louis Hospital, AP-HP, Paris, France;
21. Department of Hematology, CHU, Angers, France;
22. INSERM U892/CNRS 6299, Angers University, Angers, France;
23. Department of Genetics, Bretagne-Atlantique Hospital, Vannes, France;
24. Department of Pediatric Hematology and Oncology, CHRU, Lille, France;
25. Department of Pediatrics, National University Hospital, Singapore;
26. Department of Pediatric Hematology and Oncology, CHU, Toulouse, France;
27. Laboratory of Hematology, Gustave Roussy, Villejuif, France;
28. Department of Hematology, Necker-Enfants Malades University Hospital, AP-HP, Paris, France;
29. INSERM UMR1163 and CNRS ERL 8254, Imagine Institut, Sorbonne Paris Cité, Paris, France;
30. Descartes University, Paris, France; and
31. Department of Pediatric Hematology and Oncology, Trousseau Hospital, AP-HP, Paris, France