What causes Muir-Torre syndrome ?
What causes Muir-Torre syndrome? Muir-Torre syndrome is a subtype of Lynch syndrome and may be caused by changes (mutations) in either the MLH1, MSH2, or MSH6 gene. These genes give the body instructions to make proteins needed for repairing DNA. The proteins help fix mistakes that are made when DNA is copied before cells divide. When one of these genes is mutated and causes the related protein to be absent or nonfunctional, the number of DNA mistakes that do not get repaired increases substantially. The affected cells do not function normally, increasing the risk of tumor formation. The MSH2 gene is responsible for MTS in the majority of cases. Mutations in MLH1 and MSH2 have the most severe effect. Not everyone diagnosed with MTS will have a detectable mutation in one of these genes. Other, unidentified genes may also play a role in the development of the condition.