Microsatellite instability (MSI) status was available for 29 colorectal tumours from POLE variant heterozygotes and three from POLD1 variant heterozygotes; four (all carcinomas from POLE variant heterozygotes) of 28 CRCs (14.3%) and no adenomas were MSI + . The gene discussed is POLD1; the disease is colorectal neoplasm.