To differentiate LS from other hereditary colorectal cancer syndromes, we also included APC and MUTYH to rule out familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP), respectively, as these conditions can present with clinical features overlapping LS (43) and they are the top two most prevalent mutated genes in colorectal polyposis syndromes. Here, MUTYH is linked to Leigh syndrome.