Association study confirms two susceptibility loci for breast cancer in Chinese Han women

To date, many loci associated with breast cancer have been identified through genome-wide association studies; most of these studies were conducted using populations of European descent. Thus, it is not clear whether these susceptibility loci are also risk factors for Chinese populations. We selected and genotyped 32 single nucleotide polymorphisms (SNPs) using the Sequenom iPLEX platform in a female Chinese cohort of 3036 breast cancer cases and 3036 healthy controls. A total of 23 SNPs passed the quality control test. The associations of these SNPs with disease susceptibility were assessed using logistic regression, adjusting for age. The Bonferroni correction was used to conservatively account for multiple testing, and the threshold for statistical significance was P < 2.17 x 10(-3) (0.05/23). We confirmed ten risk-associated variants within three reported breast cancer susceptibility loci in a Chinese Han population: 5q11.2 (rs16886181, P = 5.29 x 10(-6), OR = 1.19; rs1017226, P = 5.24 x 10(-4), OR = 1.22; rs16886034, P = 2.00 x 10(-3), OR = 1.21; rs16886113, P = 1.24 x 10(-3), OR = 1.20; rs16886364, P = 9.20 x 10(-4), OR = 1.21; rs16886397, P = 1.17 x 10(-3), OR = 1.20; rs16886448, P = 1.62 x 10(-3,)OR = 1.20; and rs2229882, P = 5.14 x 10(-4), OR = 1.31), 5q14.3 (rs421379, P = 2.83 x 10(-13), OR = 1.83), and 10q26.1 (rs35054928, P = 7.73 x 10(-6), OR = 1.18). The 10q26.1 locus was found to be a susceptibility locus for breast cancer in Chinese Han women in our previous studies. 5q11.2 and 5q14.3 are confirmed here for the first time as susceptibility loci for breast cancer in Chinese Han women. This study reports three breast cancer susceptibility loci that were previously identified in European populations and are also risk factors for Chinese populations. This study may extend the genetic basis of breast cancer in Chinese Han women and highlight the contribution of multiple variants of modest effect.