There is no such thing as a typical person with Down syndrome. They do share some features but like all people they vary a lot in appearance, personality and ability. Nearly all those with the syndrome have learning difficulties (see entry Learning Disability). Some have more serious difficulties than others. It is hard to tell as babies how much they will be affected as they get older. Many children cope well with mainstream school albeit with extra support. Many adults work and some live fairly independent lives. However, most people with Down syndrome need some long-term help and support.
A number of health problems are linked to Down syndrome, including heart problems (see entry Heart Defects), thyroid problems (see entry Thyroid disorders) and reduced vision and hearing. People vary and many enjoy good health.
Most people with Down syndrome live to be 50 years of age and some live to be over 70. Alzheimer's disease (a form of dementia) affects some people with Down syndrome at an earlier age than is usual.