Severe congenital neutropenia (SCN) is characterized by low numbers of peripheral neutrophil granulocytes and a predisposition to life-threatening bacterial infections. We describe a novel genetic SCN type in 2 unrelated families associated with recessively inherited loss-of-function mutations in CSF3R, encoding the granulocyte colony-stimulating factor (G-CSF) receptor. Family A, with 3 affected children, carried a homozygous missense mutation (NM-000760.3:c.922C>T, NP-000751.1:p.Arg308Cys), which resulted in perturbed N-glycosylation and aberrant localization to the cell surface. Family B, with 1 affected infant, carried compound heterozygous deletions provoking frameshifts and premature stop codons (NM-000760.3:c.948-963del, NP-000751.1:p. Gly316fsTer322 and NM-000760.3:c.1245del, NP-000751.1:p.Gly415fsTer432). Despite peripheral SCN, all patients had morphologic evidence of full myeloid cell maturation in bone marrow. None of the patients responded to treatment with recombinant human G-CSF. Our study highlights the genetic and morphologic SCN variability and provides evidence both for functional importance and redundancy of G-CSF receptor-mediated signaling in human granulopoiesis.

doi.org/10.1182/blood-2013-11-535419, hdl.handle.net/1765/58671
Blood
Department of Hematology

Triot, A., Järvinen, P., Arostegui, J., Murugan, D., Kohistani, N., Díaz, J. Á., … Klein, C. (2014). Inherited biallelic CSF3R mutations in severe congenital neutropenia. Blood, 123(24), 3811–3817. doi:10.1182/blood-2013-11-535419