(B) H-scores of immunohistochemical (IHC) staining for the mtDNA-encoded MT-CO1 protein across different subtypes of kidney cancers (pRCC, papillary RCC; chRCC, chromophobe RCC) **, p<0.01, ***, p<0.001, ****, p<0.0001, t-test. The gene discussed is MT-CO1; the disease is kidney cancer.