Deficiencies in MMR can occur through either a germline mutation in an MMR gene (MLH1, MSH2, MSH6 and PMS2), resulting in Hereditary Nonpolyposis Colorectal Cancer (HNPCC) also known as Lynch syndrome, however, this condition occurs more commonly through sporadic epigenetic inactivation of MLH1 [3]. The gene discussed is MRC1; the disease is hereditary nonpolyposis colon cancer.