GATA1 and anemia (phenotype): GATA1, a transcription factor that regulates erythroid differentiation, interacts with a variety of hematopoietic transcription factors and is involved in the regulation of erythropoiesis genes such as heme biosynthetic enzymes, hemoglobin, EpoR, and anti-apoptotic protein (Bcl-xL) (47–51), and GATA1-deficient mice exhibited severe anemia and eventual death (48).