Genetic Variants at 6p21.1 and 7p15.3 Identified by GWASs of Multiple Cancers and Ovarian Cancer Risk: a Case-control Study in Han Chinese Women

A recent study summarized several published genome-wide association studies (GWASs) of cancer and reportedtwo pleiotropic loci at 6p21.1 and 7p15.3 contributing to multiple cancers including lung cancer, noncardia gastriccancer (NCGC), and esophageal squamous-cell carcinoma (ESCC) in Han Chinese. However, it is not knownwhether such genetic variants have similar effects on the risk of gynecologic cancers, such as ovarian cancer.Hence, we explored associations between genetic variants in 6p21.1 and 7p15.3 and ovarian cancer risk in HanChinese women. We performed an independent case-control study by genotyping the two loci (rs2494938 A > Gat 6p21.1 and rs2285947 A > G at 7p15.3) in a total of 377 ovarian cancer cases and 1,034 cancer-free controlsusing TaqMan allelic discrimination assay. We found that rs2285947 at 7p15.3 was significantly associated withrisk of ovarian cancer with per allele odds ratio (OR) of 1.33 [95% confidence interval (CI): 1.08-1.64, P=0.008].However, no significant association was observed between rs2494938 and ovarian cancer risk. Our results showedthat rs2285947 at 7p15.3 may also contribute to the development of ovarian cancer in Han Chinese women,further suggesting pleiotropy of 7p15.3 in multiple cancers.