Statistics from Altmetric.com
Ma et al1 comprehensively assessed the association of previously reported genetic variants with colorectal cancer (CRC) risk. The meta-analyses revealed strong evidence for association with rare MUTYH variants, even when excluding cases with MUTYH-associated polyposis. An article by Nieuwenhuis et al2 accurately defined the phenotypical features of MUTYH-associated polyposis. However, the study was performed on clinic-based series ascertained based on the inheritance model or the presence of polyps, which may miss additional phenotypes relevant to improve the disease characterisation and therefore, its genetic diagnosis. To illustrate this, we report a family with a clinical phenotype that resembled Lynch syndrome but was caused by MUTYH mutations.
To identify novel hereditary CRC genes, we studied an Amsterdam I family (hereditary non-polyposis CRC) with no mutations in the DNA mismatch repair (MMR) genes (figure 1, table 1). By exome sequencing performed on four cancer-affected (II.2, II.6, III.1 and III.6) and one cancer-free (III.5) family members, we identified a total of 11 unreported or rare heterozygous variants present in the cancer-affected individuals (see online supplementary table S1). One of them was MUTYH c.1147delC …