Abstract: ObjectiveTo explore the association between gene polymorphism of cytochrome P4501 B1 in exon 3 codon 432 Leu-Val and breast cancer(BC)and its clinical subgroups(breast cancer with abnormal HilitBCAH.MethodsThe BC patients were divided into four groups with different body fluid type according to Uighur medicine theory.The polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)technique was used to detect the polymorphism in exon 3 Leu432Val of CYP1B1 in 84 BC patients and 131 normal control subjects.ResultsThe frequency of genotype and allele of CYP1B1 of BC,BCAH and the control group was not significantly different(P>0.05).Compared with wild type(Leu/Leu),the susceptibility to BC for subjects with the Leu/Val+Val/Val was increased by 2.137(odds ratio OR=2.137,95% confidence intervalCI:0.969-4.717,P=0.056),and by 3.636(OR=3.636,95% CI:0.996-13.157;P=0.062)in BCAH patients.ConclusionMutation of genotype(Leu/Val+Val/Val)of CYP1B1 may be correlated to the susceptibility to BC and BCABH in Chinese Han population of Xinjiang.