APC and Leigh syndrome: 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.