GATA3 is a reliable biomarker for breast carcinomas and is frequently used to determine the tissue of origin to confirm a diagnosis (Jensen et al., 2002; Garcia-Closas et al., 2007; Bertucci et al., 1999; Liu et al., 2016; Hoch et al., 1999; Mehra et al., 2005; Sørlie et al., 2003; Chou et al., 2010; Takaku et al., 2015). This evidence concerns the gene GATA3 and breast carcinoma.