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Down syndrome

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Down syndrome

Down syndrome is a genetic condition caused by abnormal cell division in the egg, sperm, or fertilized egg. This results in an extra chromosome in some or all of the body's cells, causing some intellectual disability and health problems.

Down syndrome is also called trisomy 21, for the specific chromosome that has the abnormality. A person with Down syndrome has three copies of chromosome 21. Normally, a person has two copies.

Down syndrome usually can be detected during pregnancy or soon after birth. Chromosome tests and how a baby looks can help make a diagnosis.

Current as of: July 31, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

This information does not replace the advice of a doctor. Ignite Healthwise, LLC, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.

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© 2024 Ignite Healthwise, LLC.

This information does not replace the advice of a doctor. Ignite Healthwise, LLC, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.