Hence, we analyzed the relationship between FDX1 expression and the expression levels of the MMR gene, including MLH1, MSH2, MSH3, MSH4, MSH5, MSH6, PMS1, and PMS2. We found that FDX1 expression was significantly correlated with that of PMS2 in 17 types of cancer (Supplementary Table S1). The gene discussed is MSH4; the disease is cancer.