Down Syndrome is a rare disease. When people have Down Syndrome they have 47 chromosomes when they are supposed to have 46. A chromosome is something in your body that makes you special. About 250,000 people have Down Syndrome in U.S. You can have Heart Defects. If you have a Heart Defect you have trouble breathing. You may also have memory loss, hearing loss, and a lot of other things. You can have slanted eyes, a short neck, a small mouth, and small hands and feet. They learn how to walk and talk later then normal children. There is no cure for Down Syndrome. I hope now you know what Down Syndrome is!