Background: The CYP1B1 gene is a polymorphic member of the P450 gene family and is considered to be a candidate gene for cancers of various types.
Objective: We inquired whether four SNPs in the CYP1B1 gene, alone or in combination, might be associated with breast cancer risk in Poland.
Methods: We genotyped 2017 cases of breast cancer and 876 controls, for four SNPs in the CYP1B1 gene. Genotype and haplotype frequencies were compared in cases and controls.
Results: In combinations of the R48G, A119S and L432V SNPs, four of the eight CYP1B1 haplotypes were more common in controls than in cases and each of these appeared to have a significant protective effect. A large reduction in risk was observed for women who were homozygous for one of these four haplotypes (OR = 0.2; 95%; CI = 0.05-0.5; P = 0.001) compared to women who were homozygous for the most common haplotype. In contrast, women who were homozygous for the GTC haplotype were at increased risk (OR = 1.5; 95%; CI = 1.0-2.1; P = 0.03) compared to women with the most common haplotype.
Conclusions: The CYP1B1 gene appears to influence breast cancer susceptibility in Poland.