Light micrograph through a section of human stomach lining showing juvenile polyposis syndrome (JPS). This is an inherited disorder marked by growths called polyps, which grow on the lining of the gastrointestinal tract. These polyps can occur anywhere in the GI tract, from the stomach to the rectum. The word 'juvenile' refers to the way the polyps look under the microscope and not to the age of people who get the disorder.