How was Down syndrome discovered?

John Langdon Down, a British physician, was the first person to fully describe the syndrome in 1866. It is one of the most common chromosomal abnormalities. The genetic cause of Down syndrome, an extra copy of chromosome 21, was identified by researchers in 1959.

What causes Down syndrome?

There is no known cause for Down syndrome. Down syndrome is a naturally occurring chromosomal arrangement that has always been a part of the human condition. The sole characteristic shared by all people with Down syndrome is the presence of extra genetic material associated with the 21st chromosome. This happens because of an error during cell division when the egg and sperm first meet. The effects of that extra genetic material vary greatly from individual to individual.

What is the likelihood of having a baby with Down syndrome? What is the frequency of Down syndrome in births?

In Canada, approximately 1 in every 800 live births results in a Down syndrome determination. Eighty per cent of babies born with Down syndrome are born to women under the age of 35.

Is Down syndrome a disease? Is Down syndrome curable?

Down syndrome is not a disease, disorder, defect or medical condition and therefore does not require treatment, prevention or a cure. It is inappropriate and offensive to refer to people with Down syndrome as “afflicted with” or “suffering from” it.

Is Down syndrome a disability? Are there disabilities associated with Down syndrome?

The extra genetic material from Down syndrome results in a developmental disability, but it is impossible to suggest the level to which this will occur. Some individuals with Down syndrome may have other disabilities, however, they are not directly linked to having Down syndrome.

Why do people with Down syndrome look similar?

Some people with Down syndrome may share similar physical features. However, people with Down syndrome predominantly look like other members of their families.