In CORGI 1% of patients screened were found to carry POLE Leu424Val, POLD1 Ser478Asn, POLD1 Asp316Asn or POLD1 Leu474Pro and in QUASAR 2/VICTOR clinical trials 0.1% of CRC patients screened carried POLE Leu424Val or POLD1 Ser478Asn. Here, POLD1 is linked to colorectal carcinoma.