MLH1 is utilized by normal proliferating cells to repair point mutations that may occur during DNA replication. MLH1 deficiency is often the result of germline mutations in MMR deficient individuals. Absence of MLH1 has also been reported in 10-15% of sporadic colorectal carcinomas. Individuals lacking the MLH1 protein are predisposed for hereditary non-polyposis colorectal cancer (HNPCC). HNPCC is an autosomal dominant disorder associated with a high risk of developing colorectal cancer.