Five common single nucleotide polymorphisms in the PALB2 gene and susceptibility to breast cancer in eastern Chinese...

Certain rare germline mutations in the PALB2 gene have been confirmed to increase susceptibility to breast cancer in diverse populations, but it has not been very clear that whether some common polymorphic variants in PALB2 also increase breast cancer risk. We conducted a case-control study to validate the association of common variations in the PALB2 gene and breast cancer in eastern Chinese population. A total of six common single nucleotide polymorphisms (rs8053188, rs16940342, rs249954, rs447529, rs249935, and rs3096145), which tagged the known common variants (minor allele frequency >0.1) of PALB2, were genotyped among 660 cases and 756 cancer-free controls by SNPstream assay. Except rs3096145, other five SNPs passed the quality assessment criteria with genotyping call rate >95%. Genotype and allele frequencies were statistically different between cases and controls for PALB2 rs447529 and rs249935. PALB2 rs249935 G allele was related to a 1.21-fold (95% confidence interval = 1.02-1.43) increase in risk for each 'A' allele carried (P = 0.029). Based on the dominant inheritance model tests, we found that compared with rs447529 CC homozygotes, the variant homozygote GG and heterozygote GC carriers had a 0.43-fold decreased risk of breast cancer (95% confidence interval = 0.24-0.78, P = 0.005). Combined with the results of the former study, our findings further verified that some common PALB2 polymorphisms may contribute to the etiology of breast cancer in Chinese women, so other large studies are warranted to confirm these observations in different ethnic populations.