The two-in-one hit model of the short-cut carcinogenesis of colorectal carcinomas in MLH1-associated Lynch syndrome

In a recently published study a new genetic hypothesis was established that explained the existence of CTNNB1 mutations in Lynch syndrome-associated colorectal carcinomas (MLH1-LS-CRC). This hypothesis states that a mitotic recombination on chromosome 3p simultaneously leads to inactivation of the mismatch repair gene MLH1 and to the activation of CTNNB1. This explains the increased frequency of CTNNB1 mutations in MLH1-LS-CRC compared with other colon carcinomas. To test this …