Clinical presentations that should prompt genetic screening for GATA2 deficiency include idiopathic cytopenia—affecting neutrophils, monocytes, dendritic, B, and NK cells—idiopathic CD4 lymphocytopenia, MDS, aplastic anemia in adolescents and young adults, pulmonary alveolar proteinosis, congenital lymphedema, and marked susceptibility to human papillomaviruses and nontuberculous mycobacteria, among others (3, 14). The gene discussed is GATA2; the disease is myelodysplastic syndrome.