MSH2 gene expression level results such as BLCA, BRCA, LAML, LGG, LUAD, LUSC, PRAD, skin cutaneous melanoma (SKCM), and STAD were significantly and positively correlated with TMB, while ESCA, KIRC, KIRP, THCA, and THYM showed a negative correlation between MSH2 gene expression levels and TMB. The gene discussed is MSH2; the disease is cutaneous melanoma.