No Association between Ovarian Cancer Susceptibility Variants and Breast Cancer Risk among Chinese Women

Background: As breast and ovarian cancers may have similar etiologies, this study aimed to evaluate the hypothesis that breast cancer shares common genetic susceptibility variants with ovarian cancer. Methods: Ten genetic variants in 9 loci were previously identified to be associated with ovarian cancer risk among Caucasian women; an additional 353 variants in high linkage disequilibrium (r2≥0.6) among Han Chinese were identified. Data were available from the Affymetrix Genome Wide Array (6.0) or MACH imputation for 25 and 78 common genetic variants (minor allele frequency (MAF) ≥0.05), respectively. Associations with breast cancer risk were evaluated by additive logistic regression models among 2,918 breast cancer cases and 2,324 controls. Results: No associations with breast cancer risk were evident for 103 ovarian cancer susceptibility variants in five loci. Four loci were not evaluated, as they included only rare variants (MAF<0.05). Conclusions: Ovarian cancer susceptibility variants identified in Caucasian women were not associated with breast cancer risk among 5,242 Chinese women. Impact: These findings suggest that breast and ovarian cancer may not share common susceptibility variants among Chinese women.