Due to the requirement for GATA2 in renewal of the adult stem cells, it is thought that depletion of the stem cell pool leads to subsequent lymphopenia, and in vitro differentiation experiments demonstrate an NK cell intrinsic role for GATA2 through the phenocopying of the CD56bright NK cell subset loss in NK cells derived from patient CD34+ HSC (33). The gene discussed is GATA2; the disease is lymphopenia.