Particularly, SNPs PvuII c454-397T>C (NCBI ID: rs2234693) and XbaI c454-351A>G (NCBI ID: rs9340799) present on intron 1 of ESR1 gene have been associated to several estrogen-sensitive traits which include many pathological conditions such as abortion, breast cancer, endometriosis, myocardial infarction, and thromboembolism [6,9–17]. The gene discussed is ESR1; the disease is breast cancer.