In the intergenic region between BRCA1 and NBR2 genes, a minimal 56-bp EcoRI–HaeIII fragment has been delineated to act as a bi-directional promoter and it induces transcription in the NBR2 gene direction 2–4-fold higher than that in the BRCA1 direction in all tested cell lines (including cervical carcinoma, colon carcinoma, and mammary carcinoma cells). Here, BRCA1 is linked to breast carcinoma.