What are the other Names for this Condition? (Also known as/Synonyms)

• Chromosome 21 Disorders

What are Disorders of Chromosome 21? (Definition/Background Information)

There are many disorders that are caused by abnormalities on chromosomes 21. Some are more common than others. Researchers know more about certain chromosomal disorders than others. Information is constantly being added through research, better documentation, and increased awareness.

Chromosomes are microscopic protein structures present in each cell nucleus that carry genetic information in the form of DNA (deoxyribonucleic acid). Humans have 46 chromosomes in the cell nucleus, in 23 pairs, of which one pair is named the sex chromosome. In males, it is designated XY, for chromosome X and chromosome Y; while, in females, it is designated XX, for a pair of chromosome X. The other 22 pairs of chromosomes are numbered chromosome 1 through 22.

During conception, the embryo inherits one copy of each chromosome from each parent (i.e., mother and father). Any alteration in the chromosome numbers or structure can result in mild to severe genetic abnormalities. Specialized genetic testing techniques are often required to confirm the diagnosis.

Chromosome 21 Disorders are disorders involving chromosome 21. Some of the disorders include:

Chromosome 21q Deletion Syndrome: Chromosome 21q Deletion Syndrome, also known as 21q deletion syndrome, is a genetic disorder caused by the loss of genetic material on the long arm of chromosome 21. It can result in various health issues, including congenital heart defects. Common signs and symptoms may include intellectual disability, developmental delays, distinctive facial features, and other physical abnormalities. Treatment focuses on managing the specific symptoms and providing supportive care to address developmental, educational, and medical needs.

Ring Chromosome 21 Syndrome: Ring Chromosome 21 Syndrome is a rare genetic disorder characterized by a ring-shaped chromosome 21. It can lead to various health issues, but its association with congenital heart defects is unclear. Common symptoms may include intellectual disability, developmental delays, distinctive facial features, and other physical and neurological abnormalities. Treatment focuses on managing specific signs and symptoms and providing supportive care to address developmental, educational, and medical needs.

This article is a resource with links to other more specific disorders. Information on each Chromosome 21 Disorder may be viewed by clicking on the respective subtypes (above).

Information to join DoveMed’s patient forum called MyCIrcles to learn and manage the condition is also included. We are adding more information to this page periodically. Please bookmark this page for future reference and visit for updated content.

You can join Chromosome Disorders MyCircles patient forum by visiting here: https://www.dovemed.com/mycircles/circles/all