GATA3

GATA3 is a transcription factor encoded by the GATA3 gene in humans. It belongs to the GATA family of zinc finger transcription factors that bind the consensus DNA sequence WGATAR and regulate gene expression during development and differentiation. The GATA3 gene is located on chromosome 10p14 and encodes a protein with two zinc finger DNA-binding domains and transactivation regions.

GATA3 is expressed in multiple tissues, with prominent roles in the immune and mammary systems. In the immune system, GATA3 is essential for the development of T cells and for the differentiation of CD4+ T helper cells toward the Th2 lineage, promoting cytokines such as IL-4, IL-5, and IL-13. In the mammary gland, GATA3 controls morphogenesis and luminal cell differentiation; its expression is characteristic of many ER-positive breast cancers and is commonly used as a diagnostic marker. GATA3 also contributes to kidney and inner ear development, and its deficiency in humans can contribute to disease.

Clinical significance: GATA3 haploinsufficiency causes HDR syndrome—hypoparathyroidism, deafness, and renal dysplasia. In oncology, GATA3 expression supports classification of breast and urothelial carcinomas and is typically associated with a luminal, hormone receptor–positive phenotype in breast cancer; prognosis is context-dependent and influenced by multiple factors.