RAC2 mutations and immune deficiency – functional spectrum of an international cohort

Mutations in RAC2 were first identified in neonates carrying RAC2 dominant negative p.D57N, who presented with severe neutrophil defects and T-cell lymphopenia. Subsequently, dominant-activating mutations were reported in patients with combined immunodeficiency/immunodysregulation (CIID) or severe combined immunodeficiency (SCID). We assembled an international cohort of 48 published and unpublished patients with RAC2 mutations to characterize the spectrum of disease.