Among these cancer types, SKCM, PAAD, LUSC, LUAD, FDX1 expression, and MSI had a significant negative correlation, and the PAAD coefficient was the highest; conversely, in DLBC, HNSC, KIRC, STAD, and UCEC, FDX1 expression was positively correlated to MSI, and the DLBC coefficient was the highest. The gene discussed is FDX1; the disease is cancer.