IFNA21 and neoplasm: Notable, HR mutated tumors contained increased IFNβ (IFNB1) and IRF8 (type I IFN positive feedback loop) mutations, while MMR mutated tumors contained increased IFNα (IFNA5, IFNA14, IFNA21) and IFNAR2 (type I IFN receptor) mutations (Supplementary Figure 2A–2C), thereby indicating that while mutations in DNA repair genes are linked to increased tumor mutation count and TILs, they also may represent tumors with increased type I IFN gene mutations.