Down Syndrome
Down syndrome, also called Trisomy 21, is caused by an extra chromosome number 21 in every cell of the body. It is the most common chromosome abnormality in liveborn infants; in an unscreened population about 1 in every 800 babies is born with Down syndrome. Children with Down syndrome have characteristic facial features, low muscle tone and mental retardation. About half of children with Down syndrome also have a birth defect, with heart defects being the most common. People with Down syndrome are also more likely to have medical problems, including difficulties with vision and hearing. Each person with Down syndrome is different and there is no way to know before a child is born how serious the medical and mental disabilities will be. There is no cure for Down syndrome, but resources are available to help people with Down syndrome and their families.
For more information about Down syndrome:
National Down Syndrome Society
National Down Syndrome Congress
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