GATA2 and Decreased total monocyte count: GATA2 haploinsufficiency occurs due to inactivation or loss of one copy of GATA2, and has been associated with: monocytopenia and nontuberculous mycobacterial (NTM) infections (MonoMac Syndrome), dendritic/monocyte/B/Natural Killer (NK)-cell lymphoid deficiencies (DCML), familial myelodysplastic syndrome, Emberger syndrome, and classical NK cell deficiency (5).