The 2 main missense mutations c.1145G>A, p.Gly382Asp and c.494A>G, p.Tyr165Cys were associated with the development of colorectal adenomas/serrated polyps in these monoallelic carriers.
Here, we report the identification of seven further unrelated patients with >100 colorectal adenomas (six with colorectal cancer) and biallelic germline mutations in MYH: four were homozygous for truncating mutations, two were homozygous for Y165C and one was a Y165C/G382D compound heterozygote.