Triple negative breast cancer (TNBC) in humans is a distinct subset of breast cancer that is defined by the lack of immunohistochemical (IHC) expression of the oestrogen receptor (ER) and progesterone receptor (PR) and a lack of human epidermal growth factor receptor 2 (HER2) overexpression[1]. The gene discussed is PGR; the disease is triple-negative breast carcinoma.