The DNA mismatch repair (MMR) system guards against genomic instability, and mutations in the human MMR genes MutS homolog 2 (MSH2) and MutL homolog 1 (MLH1) are the cause of the majority of hereditary nonpolyposis colorectal cancer (HNPCC) [7]. Here, MSH2 is linked to hereditary nonpolyposis colon cancer.