CYP1A1 and breast cancer: For example, an increased breast cancer risk associated with the CYP1A1*2 (Ile462Val) allele and smoking was observed in Caucasian women [35,36], whereas Chinese and Japanese women carrying the CYP1A1*2 (Ile462Val) allele have a significantly reduced risk of breast cancer as compared with carriers of the wild-type allele [37].