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Down Syndrome

What is Down syndrome?

Down syndrome is a condition in which a person has an extra chromosome or an extra piece of a chromosome. This extra copy changes how a baby's body and brain develop. It can cause both mental and physical challenges during their lifetime. Even though people with Down syndrome might act and look similar, each person has different abilities.

What causes Down syndrome?

Chromosomes are tiny "packages" in your cells that contain your genes. Genes carry information, called DNA, that controls what you look like and how your body works. People with Down syndrome have an extra copy of chromosome 21. In some cases, they may have an extra copy of part of the chromosome. Having an extra copy of a chromosome is called trisomy. So sometimes Down syndrome is also called trisomy 21.

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Results 1 - 10 of 302 for Trisomy 21
  1. Down Syndrome (National Library of Medicine)  
    ... trisomy. So sometimes Down syndrome is also called trisomy 21. Down syndrome is usually not inherited. It happens ...
    https://medlineplus.gov/downsyndrome.html - Health Topics
  2. Down syndrome 
    ... 21. This form of Down syndrome is called trisomy 21. The extra chromosome causes problems with the way the body and brain develop. Down syndrome is one of the most common causes of ...
    https://medlineplus.gov/ency/article/000997.htm - Medical Encyclopedia
  3. Quadruple screen test 
    ... due to a problem such as: Down syndrome (trisomy 21) Edwards syndrome (trisomy 18)
    https://medlineplus.gov/ency/article/007311.htm - Medical Encyclopedia
  4. Down Syndrome Tests: MedlinePlus Medical Test 
    ... This common form of Down syndrome is called trisomy 21. "Trisomy" means having three copies of a chromosome ... Irving (TX): American Pregnancy Association; c2021. Down Syndrome: Trisomy 21; [ cited 2022 Aug 23]; [about 8 screens]. Available ... Kenilworth (NJ): Merck & Co. Inc.; c2022. Down Syndrome (Trisomy 21); [revised 2021 Dec; cited 2022 Aug 23]; [about ...
    https://medlineplus.gov/lab-tests/down-syndrome-tests - Medical Tests
  5. Down syndrome 
    ... older. Most cases of Down syndrome result from trisomy 21, which means each cell in the body has ... not inherited. When the condition is caused by trisomy 21, the chromosomal abnormality occurs as a random event ...
    https://medlineplus.gov/genetics/condition/down-syndrome - Genetics
  6. About Down Syndrome (National Down Syndrome Society)  
    Down Syndrome/Start Here ... Down Syndrome ... National Down Syndrome Society ... In every cell in the human body there is a nucleus, where genetic material is stored ...
    https://ndss.org/about - External Health Links
  7. National Down Syndrome Society (National Down Syndrome Society)  
    ... Athlete Ambassador Team Get Involved Join the NDSS Down Syndrome Advocacy Conference! Register here NDSS empowers individuals with Down syndrome and their families by driving policy change, providing ...
    https://ndss.org - Other Resources
  8. Nuchal translucency test 
    ... Measuring this thickness helps assess the risk for Down syndrome and other genetic problems in the baby. ... back of their neck. In a baby with Down syndrome or other genetic disorders, there is more fluid ...
    https://medlineplus.gov/ency/article/007561.htm - Medical Encyclopedia
  9. What Causes Down Syndrome? From the National Institutes of Health (Eunice Kennedy Shriver National Institute of Child Health and Human Development)  
    Down Syndrome/Related Issues ... Down Syndrome ... Down syndrome is caused by a random error in cell division that results in the presence of an extra copy of chromosome ...
    https://www.nichd.nih.gov/health/topics/down/conditioninfo/causes - External Health Links
  10. About Down Syndrome From the National Institutes of Health (National Human Genome Research Institute)  
    Down Syndrome/Genetics ... Down Syndrome ... National Human Genome Research Institute ... From the National Institutes of Health ... Down syndrome is a chromosomal condition ...
    https://www.genome.gov/Genetic-Disorders/Down-Syndrome - External Health Links
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