[5] It regulates many genes that are critical for the embryonic development, self-renewal, maintenance, and functionality of blood-forming, lymphatic system-forming, and other tissue-forming stem cells.

[6][7] Inactivating mutations of the GATA2 gene cause a reduction in the cellular levels of GATA2 and the development of a wide range of familial hematological, immunological, lymphatic, and/or other disorders that are grouped together into a common disease termed GATA2 deficiency.

For example, in hematological stem cells, GATA2 transcription factor itself binds to one of these sites and in doing so is part of functionally important positive feedback autoregulation circuit wherein the transcription factor acts to promote its own production; in a second example of a positive feed back circuit, GATA2 stimulates production of Interleukin 1 beta and CXCL2 which act indirectly to simulate GATA2 expression.

The human gene is also expressed in endothelium, some non-hematological stem cells, the central nervous system, and, to lesser extents, prostate, endometrium, and certain cancerous tissues.

Likewise, the role of GATA2 overexpression in non-familial AML as well as development of the blast crisis in chronic myelogenous leukemia and progression of prostate cancer is not understood.

This mutation substitutes valine for leucine in the 359 amino acid position (i.e. within the N-ZnF site) of the transcription factor and has been detected in individuals undergoing the blast crisis of chronic myelogenous leukemia.

[10][11] The reason for the overexpression of GATA2 that begins in the early stages of prostate cancer is unclear but may involve the ability of FOXA1 to act indirect to stimulate the expression of the GATA2 gene.

For example, displacement of GATA2 bond to this sequence by the GATA1 transcription factor appears important for the normal development of some types of hematological stem cells.

In all events, the actions of GATA2, particularly with referenced to its interactions with many other gene-regulating factors, in controlling its target genes is extremely complex and not fully understood.

[6][14][15][16] Familial and sporadic inactivating mutations in one of the two parental GATA2 genes causes a reduction, i.e. a haploinsufficiency, in the cellular levels of the GATA2 transcription factor.

[6][7] The various presentations of GATA2 deficiency include all cases of Monocytopenia and Mycobacterium Avium Complex/Dendritic Cell Monocyte, B and NK Lymphocyte deficiency (i.e. MonoMAC) and the Emberger syndrome as well as a significant percentage of cases of familial myelodysplastic syndrome/acute myeloid leukemia, congenital neutropenia, chronic myelomonocytic leukemia, aplastic anemia, and several other presentations.

[19] This epigenetic gene silencing also occurs in certain types of non-small-cell lung carcinoma and is suggested to have a protective effect on progression of the disease.