Specifically, MMR genes negatively correlated with HRD included the DNA polymerase delta 4, accessory subunit gene (POLD4) in BLCA (rho ═ −0.11, P value ═ 0.04) and in GBM (rho ═ −0.19, P value ═ 0.04); MutL homolog 3 (MLH3) in BRCA (rho ═ −0.23, P value ═ 1.22E--12), in KIRC (rho ═ −0.14, P value ═ 0.01), and in MESO (rho ═ −0.23, P value ═ 0.05); MutL homolog 3 (MLH1) in BRCA (rho ═ −0.18, P value ═ 6.39E--08), in HNSC (rho ═ −0.12, P value ═ 0.01), and in LUAD (rho ═ −0.12, P value ═ 0.01). The gene discussed is MLH3; the disease is glioblastoma.