Trisomy 21 Overview
Another name for Trisomy 21 is Down's Syndrome.
What is Down's syndrome?
A person with Down's syndrome has an extra copy of one of the chromosomes, which results in mental retardation, as well as other symptoms. Chromosomes contain genetic material that directs the actions of cells. Normally, human cells have 23 pairs of chromosomes, resulting in 46 chromosomes. One of each pair comes from the mother, and one of each pair comes from the father. Down's syndrome describes the symptoms and signs displayed by someone who has an extra 21st chromosome, which results in 47 total chromosomes. In the US, about 1 out of 1,000 infants is born with Down's syndrome.
What are the symptoms of Down's syndrome?
Symptoms of Down's syndrome may include small head for size, flattened nose, large tongue, slanted eyes, growth retardation, mental retardation, shorter than average height, vision problems, hearing loss, and symptoms of heart disease.
How does the doctor treat Down's syndrome?
There is no cure for Down's syndrome. Treatment for Down's syndrome may include: social services, special education, and the treatment of deafness and underlying heart disease.
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