Genetic variant rs1058240 at the microRNA-binding site in the GATA3 gene may regulate its mRNA expression.

The GATA binding protein 3 (GATA3) is a member of a family of 6 GATA dual zinc finger transcription factors (GATA1-6), which are required for the development and morphogenesis of the mammary gland. GATA3 is considered to play a dual role in oncogenesis and cancer development, whereas somatic mutations have been reported in breast cancer. Variants of the genetic 3' untranslated region (3'UTR) microRNA (miRNA) binding sites have been associated with breast cancer risk. However, the roles of genetic variants in the gene 3'UTR and its post-transcriptional regulation have not been fully elucidated. We discovered that rs1058240 in the 3'UTR displayed potential miRNA binding sites and this variant was found to be significantly associated with mRNA expression (P=2.36E-07), suggesting that rs1058240 may be a putative variant mediating the post-transcriptional regulation of the target gene. Further studies investigating the regulatory mechanism of transcriptional activity are required to design novel strategies against breast cancer cell growth and differentiation.