Of these, four methylation sites including cg05413957 (GRID2IP), cg07020967 (TMEM117), cg10674684 (intergenic region), and cg20100408 (HLA-DP) were selected as the optimal model sites for the prognostic assessment of patient with GC by LASSO regression and multivariate Cox regression analysis. Here, HLA-DPB1 is linked to gastric cancer.