SMAD4 and juvenile polyposis syndrome: As regards hamartomatous polyposis syndromes (JPS, PJS, and PHTS), current NCCN guidelines recommend genetic testing for disease-causing genes (BMPR1A, PTEN, SMAD4, and STK11) in patients who develop clinical manifestations that are specific for each syndrome, with the presence of more than two hamartomatous CPs being a common clinical criterion for all of these syndromes [12].