Targeted sequencing and functional interrogation identified novel variant at 12q14.2 associated with risk of ovarian cancer in Han Chinese women.

Chromosome 12q14.2 has been reported as a potential risk locus for epithelial ovarian cancer (EOC) in genome-wide association study (GWAS). We performed targeted sequencing around the rs11175194 at chromosome 12q14.2 and identified five potential risk variants. The association between these five variants and EOC risk was evaluated in 893 EOC cases and 1292 controls. We identified that rs11175195 (P = 1.94 × 10-6, OR = 1.36, 95% CI = 1.20-1.54) was significantly associated with EOC risk in validation study and after meta-analysis with previous GWAS data, rs11175195 reached genome-wide significant level (P < 5 × 10-8). Functional annotation and expression quantitative trait loci analysis prioritized rs11175194 as a causal variant at this locus. The presence of G-rs11175194 risk allele increased binding affinity of the transcription factor NR1H4 and upregulate SRGAP1 gene expression. Overexpression of SRGAP1 promotes the proliferation and invasion in ovarian cancer cell lines. In conclusion, we identified a novel susceptibility locus of ovarian cancer and revealed a potential molecular mechanism for ovarian cancer carcinogenesis. These results may provide a potential biomarker and therapeutic target for ovarian cancer.