1q21.1 duplication

Also known as

A 1q21.1 microduplication is a very rare genetic condition in which a tiny extra piece of one of the chromosomes is found in the cells of the body. The tiny extra bit increases the risk of learning and development difficulties. But there is wide individual variation. People with a 1q21.1 microduplication range from people with no symptoms to others with developmental delay and health problems.

Condition details

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Photos of affected individuals

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  • No baby imageBaby
  • No toddler imageToddler
  • No child 4-10 imageChild 4-10
  • No child 10-18 imageChild 10-18
  • No adult imageAdult

Typical age range of first manifestation

  • Can manifest in Baby
  • Does not manifest in Toddler
  • Does not manifest in Child 4-10
  • Does not manifest in Child 10-18
  • Does not manifest in Adult


Lay terms Clinical terms
  • Low muscle tone Low set ears Small jaw Large head Rocker bottom feet Reflux
Lay terms Clinical terms
  • Low muscle tone Speech delay Developmental delay
Child 4-10
Lay terms Clinical terms
  • Hyper mobility Low muscle tone Autistic tendencies
  • Macrocephaly

Affected genes identified to date

Inheritance patterns

Are carriers affected?

How many are affected?


Support groups and organisations

Tel 01883 723356

Known experts

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