What is Down syndrome?

People with Down syndrome are people first of all, and require the love and care on which all of us thrive. People with Down syndrome can now lead more happy, independent and productive lives than ever dreamed possible, if we recognise their abilities and support their needs.

Down syndrome affects people of all ages, races and economic levels, occurring once in approximately every 860 babies born throughout the world, male and female alike. It is one of the most common known causes of intellectual disability.

Down syndrome is caused by an extra copy of chromosome 21 inside each of the body's cells (hence the biological term, Trisomy 21). It is a chromosomal accident, not known to be caused by anything the parents may have done before or during pregnancy. Down syndrome is recognisable at birth because of some typical physical characteristics and diagnosis will be confirmed by chromosome analysis.

While people with Down syndrome do have features in common, they also closely resemble their parents and family. Many characteristics are attributed to Down syndrome, but any one person will have only some of them - each person is an individual, with a unique appearance, personality and set of abilities. The extent to which each child shows the physical characteristics of the syndrome is no indication of his or her intellectual capacity.

• Welcoming your Baby with Down Syndrome - our page of links to family stories and resources
• Brighter Tomorrows - a website designed to support families with accurate information about Down syndrome