Heterozygous germline mutations in GATA2, a highly pleiotropic gene that encodes the hematopoietic transcription factor GATA2 (215), revealed to be the unifying genetic cause of four apparently distinct syndromes: monocytopenia with M. avium complex (MonoMAC) (216), dendritic cell, monocyte, B and NK lymphoid deficiency (DCML) (217), primary lymphedema with myelodysplasia (Emberger syndrome) (218), and familial myelodysplastic syndrome/acute myeloid leukemia (219). Here, GATA2 is linked to Decreased total monocyte count.