Fig. 1From: POLE/POLD1 mutation and tumor immunotherapyUltra high mutation state of microsatellite stability. The most common mutation in MSI-H tumors is frameshift deletion mutation, whereas the most common mutation in POLE/POLD1-mutant tumors is missense mutation. The loss of mismatch repair ability combined with the loss of replication polymerase proofreading ability can produce defects of full replication repair, resulting in ultra-high mutation with MSSBack to article page