OBJECTIVEAromatase, encoded by CYP19A1, play an important role in estrogens biosynthesis from androgens. The present study is to investigate effect of R264C single nucleotide polymorphism in CYP19A1 gene on genetic susceptibility for hereditary breast cancer without BRCA1/2 mutant.

METHODSOne hundred and fourteen BRCA1/2 -negative hereditary breast cancer patients from independent families and 121 age-matched healthy control subjects were analyzed. Genotype analysis was performed through polymerase chain reaction (PCR) and then DNA direct sequencing. The odd-ratios (OR) and 95% confidence intervals (CI) were calculated by unconditional Logistic regression model.

RESULTSThe frequency of R264C single nucleotide polymorphism CC, CT and TT genotype in case group and controls was 84(77.8%), 22(20.4%), 2(1.8%) and 87(77.7%), 24(21.4%), 1(0.9%), respectively. CT genotype (OR=1.16, 95%CI: 0.53-2.55) and TT genotype (OR=1.44, 95%CI: 0.12-17.15) did not confer a significantly increased risk for breast cancer. No significant association was found between T allele and susceptibility for breast cancer under analysis according to menopausal status and body mass index.

CONCLUSIONR264C polymorphism in CYP19A1 gene is not a candidate locus for low penetrance breast cancer susceptibility in Shanghai group of Chinese population and not recommended in clinical genetic test. Homozygous T allele of R264C is not common in Shanghai group of Chinese population.