e15552 Background: RPTOR is an essential scaffold for MTOR complex which is necessary for the MTOR-catalyzed phosphorylation. Methods: In this study of 1,100 gastric cancer (GCa) cases and 1,137 matched cancer-free controls, we investigated associations between eight potentially functional single nucleotide polymorphisms (SNPs) (rs3751934 C > A, rs1062935 T > C, rs12602885 G > A, rs1468032 T > A, rs1468033 A > G, rs2271610 C > G, rs2271612 C > T, and rs2878052 G > A) in RPTOR and gastric cancer risk in an Eastern Chinese Population. Results: In logistic regression analysis, a significantly increased GCa risk was associated with the rs1468032 AA variant genotype (adjusted odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.09-1.60) under a dominant model, which remained significant after correction by the false-positive reporting probability. This risk was more evident in subgroups of younger subjects, females, never smokers, never drinkers, cancers of non-cardia and stage of Ⅲ+Ⅳ. We then performed SNP-mRNA expression correlation analysis in GTEx database as well as using real-time PCR in adjacent noncancerous tissues. We found that the AA variant genotype was associated with non-significantly decreased expression of RPTOR mRNA level. Conclusions: Our results suggest that the RPTOR rs1468032 A variant may be markers for GCa susceptibility. Larger, independent studies are warranted to validate our findings.