Chromosome 1q21.1 Deletion syndrome

What is Chromosome 1q21.1 Deletion syndrome?

Chromosome 1q21.1 Deletion syndrome is a rare genetic syndrome that occurs due to microdeletions on a specific chromosome.

It affects the development of affected individuals, especially their motor skills development.

Some individuals diagnosed with microdeletion show no symptoms of the syndrome at all, the reasons for this are still being researched.

What gene change causes Chromosome 1q21.1 Deletion syndrome?

The syndrome occurs when small pieces of DNA are deleted from chromosome 1 in each cell, specifically in the q21.1 region.

It is inherited in an autosomal dominant pattern, and about 50% of cases are inherited.

In the case of autosomal dominant inheritance, just one parent is the carrier of the gene mutation, and they have a 50% chance of passing it onto each of their children. Syndromes inherited in an autosomal dominant inheritance are caused by just one copy of the gene mutation.

Microdeletion inheritance occurs when there is a deletion of several genes on a chromosome. The specific chromosome on which the deletions occur will determine the syndrome they cause.

What are the main symptoms of Chromosome 1q21.1 deletion syndrome?

  • 75% of children with the syndrome will have developmental delays. This generally affects the development of their motor skills but is often mild in most cases.
  • Facial features associated with this syndrome are a prominent forehead, a large rounded nasal tip, a long philtrum, high arched palate, a very small head, short stature, and cataracts (a clouding of the lens).
  • Seizures and hypotonia (low muscle tone) are also reasonably common symptoms of the syndrome.
  • Some individuals experience behavioral conditions, including ADHD, and autism spectrum disorder. Individuals with the syndrome may also be at higher risk of developing schizophrenia.

How is it diagnosed?

To find out if someone has a diagnosis of Chromosome 1q21.1 Deletion syndrome, it is important to have a consultation and evaluation with a clinical genetic specialist.  Specialists may also suggest specific genetic testing or other types of tests to help reach a diagnosis.  FDNA’s AI technology can help speed up the diagnostic process by analyzing facial features and other health information.

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