GATA2 (GATA Binding Protein 2) is a transcription factor that plays a crucial role in regulating genes involved in blood cell formation (haematopoiesis) and endothelial cell function. It is essential for the development and maintenance of haematopoietic stem cells and the immune system. Mutations in GATA2 are associated with several blood disorders, including GATA2 deficiency, which can cause immunodeficiency, myelodysplastic syndrome, and acute myeloid leukaemia.