Breast Cancer Association Studies in a Han Chinese Population using 10 European-ancestry-associated Breast Cancer Susceptibility SNPs

Background: Genome-wide association studies (GWAS) have identified various genetic susceptibility loci forbreast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns existbetween European and Asian populations.
Methods: Ten SNPs (rs2075555 in COL1A1, rs12652447 in FBXL17,rs10941679 in 5p12/MRPS30, rs11878583 in ZNF577, rs7166081 in SMAD3, rs16917302 in ZNF365, rs311499in 20q13.3, rs1045485 in CASP8, rs12964873 in CDH1 and rs8170 in 19p13.1) were here genotyped in 1009Chinese females (487 patients with breast cancer and 522 control subjects) using the Sequenom MassARRAYiPLEX platform. Association analysis based on unconditional logistic regression was carried out to determinethe odds ratio (OR) and 95% confidence interval (95% CI) for each SNP. Stratification analyses were carriedout based on the estrogen receptor (ER) and progesterone receptor (PR) status.
Results: Among the 10 SNPs,rs10941679 showed significant association with breast cancer when differences between the case and controlgroups in this Han Chinese population were compared (30.09% GG, 45.4% GA and 23.7% AA; P = 0.012). FourSNPs (rs311499, rs1045485, rs12964873 and rs8170) showed no polymorphisms in our study. The remaining fiveSNPs showed no association with breast cancer in the present population. Immunohistochemical tests showedthat rs2075555 was associated with ER status; the AA genotype showed greater association with ER negativethan ER positive (OR = 0.54, 95% CI, 0.29–0.99; P = 0.046). AA of rs7166081 was also associated with ER status,but showed a greater association with ER positive than negative (OR = 1.59, 95% CI = 1.04–2.44; P = 0.031).However, no significant associations were found among the SNPs and PR status.
Conclusion: In this study using aHan Chinese population, rs10941679 was the only SNP associated with breast cancer risk, indicating a differencebetween European and Chinese populations in susceptibility loci. Therefore, confirmation studies are necessarybefore utilization of these loci in Chinese.