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Genetic and Rare Diseases Information Center (GARD)


Other names people use for this condition
  • Trisomy 21
  • Down's syndrome

* This condition is not a rare disease. It is a condition about which the GARD Information Center has received a question.

Down syndrome *
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Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and poor muscle tone in infancy. The degree of intellectual disability varies, but it is usually mild to moderate. People with Down syndrome may be born with a variety of health concerns, including heart defects or digestive abnormalities. In addition, they have an increased risk of developing gastroesophageal reflux, celiac disease, hypothyroidism, hearing and vision problems, leukemia and Alzheimer disease. Down syndrome is caused by the presence of extra material from chromosome 21.  Most individuals with Down syndrome have three copies of chromosome 21, instead of the usual two copies.[1]  Researchers have identified genes that cause the characteristics of Down syndrome and are working to enhance their basic understanding of Down syndrome to continue to improve on the interventions and treatment strategies.[2]


References
  1. Down syndrome. Genetics Home Reference (GHR). 2008 Available at: http://ghr.nlm.nih.gov/condition/down-syndrome. Accessed March 9, 2012.
  2. Down syndrome. March of Dimes. 2009 Available at: http://www.marchofdimes.com/baby/birthdefects_downsyndrome.html. Accessed March 9, 2012.
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Questions & Answers (Found 6 Questions)
A list of questions from the public on rare and/or genetic diseases that have been answered by the Genetic and Rare Disease Information Center. Click on each question to find the answer.


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