APC and Familial adenomatous polyposis: The proportion of APC indels was significantly higher in the MSH3-deficient adenomas than that observed in FAP patients (p = 0.003) or in published data on sporadic adenomas (HGCA) (p < 0.0001), and was higher than in adenomas from patients with unexplained polyposis, although the latter did not reach statistical significance, probably due to low numbers of APC variants (Fig 3A).