MSH2 and Leigh syndrome: However, EpCAM (Epithelial cell adhesion molecule) gene [21] is still needed to be detected in suspected hMSH2 patients, because LS caused by hypermethylation of hMSH2 which caused by EpCAM body mutation will also lead to the loss of MMR protein expression in IHC detection, but hMSH2 mutation analysis is negative.