1. Centre de Recherche Saint‐Antoine, APHP, Armand‐Trousseau Hospital, French Registry for Severe Chronic Neutropenia, CRMR of Chronic Neutropenia, Department of Pediatrics Hematology and Oncology Sorbonne Université, Inserm Paris France
2. Department of Pathology Saint‐Antoine Hospital, APHP Paris France
3. Department of Hematology and Oncology Hôpital d'Instruction des Armées (HIA) Sainte‐Anne Toulon France
4. Department of Pathology HIA Sainte‐Anne Toulon France
5. Department of Hematology Paoli‐Calmettes Institut Marseille France
6. Inserm, Centre de Recherche Saint‐Antoine, Hématologie Biologique, Hôpital Saint‐Antoine, APHP Sorbonne Université Paris France
7. Department of Genetics, Pitié–Salpêtrière Hospital, APHP Sorbonne University Paris France
8. Department of Pathology Ambroise‐Paré Hospital, APHP Boulogne France