The mRNA expression levels of the RAD51D, PRKDC, PARPBP, RAD1, NEIL2, RAD51B, UVSSA, MBD4, and RAD17 genes in STAD tumor tissues were markedly higher than those in STAD tissues, and the difference was statistically significant (Figure 6a–f and Supplemental Figure S1a–d). Here, MBD4 is linked to gastric adenocarcinoma.