CYP1B1 and breast carcinoma: They hypothesized that CYP1B1-4326C > G (432LeuVal) polymorphism maybe the possible predictive marker of response and clinical outcome to docetaxel in CRPC patients.51 Similarly, Balmukhanov and colleagues studied the associations of polymorphisms in rs1056836 site of CYP1B1 in 181 breast cancer (BC) patients from two main ethnic groups of Kazakhstan Republic (Kazakhs and Russians).