Structure of GATA3 transcription factor. A) GATA3 consists of 444 amino acids, which contain two transactivation domains (TA1 and TA2) and two zinc fingers (ZnF1 and ZnF2). B) The second zinc-finger binds to the canonical GATA motif, WGATAR, and the residues marked in blue are responsible for contact with DNA [10, 32]. MCF7 breast cancer cell line carries a heterozygous mutation, which leads to a frameshift (D336fs) in the second zinc finger and synthesis of a truncated protein. Figure modified from Ali et al.  and Ho et al. . C) Expression of wild type (WT) and mutated (Mut) GATA3 in MCF7 and T47D cells. MDA-MB-231, breast cancer cell line, negative for GATA3 was used as a control.