MSI genes in CRC mainly involve mutations in MMR genes like MutL homolog 1 (MLH1), MutS homolog 2 (MSH2), MutS homolog 6 (MSH6), PMS1 homolog 2 (PMS2), or epithelial cellular adhesion molecule (EPCAM) (encodes a protein that regulates MSH2) with mutant forms failing to correct errors within repetitive DNA sequences [3]. The gene discussed is MSH6; the disease is colorectal carcinoma.