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Germline mutation of RPS20, encoding a ribosomal protein, causes predisposition to hereditary nonpolyposis colorectal carcinoma without DNA mismatch repair deficiency.

ABSTRACT: Little is known about the genetic factors that contribute to familial colorectal cancer type X (FCCX), characterized by hereditary nonpolyposis colorectal carcinoma with no mismatch repair defects. Genetic linkage analysis, exome sequencing, tumor studies, and functional investigations of 4 generations of a FCCX family led to the identification of a truncating germline mutation in RPS20, which encodes a component (S20) of the small ribosomal subunit and is a new colon cancer predisposition gene. The mutation was associated with a defect in pre-ribosomal RNA maturation. Our findings show that mutations in a gene encoding a ribosomal protein can predispose individuals to microsatellite-stable colon cancer. Evaluation of additional FCCX families for mutations in RPS20 and other ribosome-associated genes is warranted.

SUBMITTER: Nieminen TT

PROVIDER: S-EPMC4155505 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Aberrant DNA methylation in hereditary nonpolyposis colorectal cancer without mismatch repair deficiency.

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Microsatellite stable colorectal cancers in clinically suspected hereditary nonpolyposis colorectal cancer patients without vertical transmission of disease are unlikely to be caused by biallelic germline mutations in MYH.

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