There are several other less common hereditary conditions that confer increased risk for CRC, mainly familial adenomatous polyposis (FAP or APC-associated polyposis caused by mutations in the APC gene), MUTYH-associated polyposis (MAP; mutations in MUTYH), juvenile polyposis syndrome (JPS; BMPR1A, SMAD4), PTEN hamartoma tumor syndrome (PHTS; PTEN), Peutz-Jeghers syndrome (PJS; STK11), and polymerase proofreading-associated polyposis (PPAP; POLE and POLD1) (for review, see Valle 2017). This evidence concerns the gene PTEN and Peutz-Jeghers syndrome.