Abstract
Background
The genetic variation of gastric cancer has not been fully identified. We aimed to screen and identify common variant single nucleotide polymorphisms (SNPs) and long noncoding RNA (lncRNA) related SNPs associated with the risk of gastric cancer, and construct and evaluate prediction models based on polygenic risk score (PRS).
Methods
Non-genetic factors such as H.pylori infection, environment, and genetic factors associated with gastric cancer were screened following meta-analysis and bioinformatics,verified by frequency matched case-control study. PRS and weighted genetic risk scores (wGRS) were derived from estimation of effect size. Net reclassification improvement (NRI), integrated discrimination improvement (IDI), akaike information criterion (AIC) and bayesian information criterion (BIC) were used to evaluate model.
Results
A risk gradient was observed across quantile of the PRS, the results showed that the risk of gastric cancer in the highest 10 quantile of PRS was 3.24 folds higher than that of the general population (OR=3.24,95%CI: 2.07, 5.06). The PRS with one or more risk factors (smoking, drinking and H. pylori infection) was superior to the single genetic risk model. For NRI and IDI, the PRS combinations were significantly improved compared to wGRS model combinations (P<0.001). The model of PRS combined with lncRNA SNPs, smoking, drinking and H. pylori infection was the best fitting model (AIC=117.23, BIC=122.31).
Conclusion
Our findings indicated that the model based on PRS combined with lncRNA SNPs, smoking, drinking, and H. pylori infection had the optimal predictive ability on the risk of gastric cancer, contributing to distinguish high-risk groups from population.