22q11.2 duplication syndrome
Alternate names[edit | edit source]
22q11.2 duplication; 22q11.2 microduplication syndrome; Chromosome 22q11.2 duplication syndrome
Definition[edit | edit source]
22q11.2 duplication syndrome is a condition caused by an extra copy of a small piece of chromosome 22 which contains about 30 to 40 genes.
Cause[edit | edit source]
- People with 22q11.2 duplication have an extra copy of some genetic material at position q11.2 on chromosome 22.
- In most cases, this extra genetic material consists of a sequence of about 3 million DNA building blocks (base pairs), also written as 3 megabases (Mb).
- The 3 Mb duplicated region contains 30 to 40 genes.
- For many of these genes, little is known.
- A small percentage of affected individuals have a shorter duplication in the same region.
Inheritance[edit | edit source]
- It is inherited in an autosomal dominant manner.
- While many affected people inherit the condition from a parent, others are affected due to having a new mutation that occurs for the first time.
- In either case, the condition can be passed on to children.
Signs and symptoms[edit | edit source]
- The features of this condition vary widely, even among members of the same family (intrafamilial variability).
- Affected individuals may have intellectual or learning disability, developmental delay, slow growth leading to short stature, and weak muscle tone (hypotonia).
- Many people with the condition have no apparent physical or intellectual disabilities.
Clinical presentation[edit | edit source]
For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed.
30%-79% of people have these symptoms
- Abnormality of the pharynx
- Cleft palate(Cleft roof of mouth)
- Delayed speech and language development(Deficiency of speech development)
- Depressed nasal ridge(Flat nose)
- Downslanted palpebral fissures(Downward slanting of the opening between the eyelids)
- Epicanthus(Eye folds)
- Global developmental delay
- High forehead
- [[Hypertelorism](Wide-set eyes)
- Intellectual disability(Mental deficiency)
- Midface retrusion(Decreased size of midface)
- Muscular hypotonia(Low or weak muscle tone)
- Narrow face(Decreased breadth of face)
- Nasal speech(Nasal voice)
- Neurological speech impairment(Speech disorder)
5%-29% of people have these symptoms
- Abnormality of immune system physiology
- Anterior creases of earlobe(Earlobe crease)
- Anxiety(Excessive, persistent worry and fear)
- Aplasia/Hypoplasia of the thymus(Absent/small thymus)
- Attention deficit hyperactivity disorder(Attention deficit)
- Autism
- Displacement of the urethral meatus
- Growth delay(Delayed growth)
- Hearing impairment(Deafness)
- Hydronephrosis
- Hypoplastic left heart(Underdeveloped left heart)
- Interrupted aortic arch
- Microcephaly(Abnormally small skull)
- Micrognathia(Little lower jaw)
- Obsessive-compulsive behavior(Obsessive compulsive behavior)
- Ptosis(Drooping upper eyelid)
- Scoliosis
- Seizure
- Smooth philtrum
- Stereotypy(Repetitive movements)
- Tetralogy of Fallot
- Transposition of the great arteries
- Urethral stenosis(Narrowing of the urethra)
- Ventricular septal defect(Hole in heart wall separating two lower heart chambers)
- Wide nose(Broad nose)
Diagnosis[edit | edit source]
The duplication is not detectable by karyotype and most cases are identified by a technique known as chromosomal microarray. [1][1].
Treatment[edit | edit source]
Treatment depends on the symptoms in each person and includes an individualized educational program.[2][2].
References[edit | edit source]
- ↑ Firth HV. 22q11.2 Duplication – RETIRED CHAPTER, FOR HISTORICAL REFERENCE ONLY. 2009 Feb 17 [Updated 2013 Nov 21]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK3823/
- ↑ Firth HV. 22q11.2 Duplication – RETIRED CHAPTER, FOR HISTORICAL REFERENCE ONLY. 2009 Feb 17 [Updated 2013 Nov 21]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK3823/
NIH genetic and rare disease info[edit source]
22q11.2 duplication syndrome is a rare disease.
22q11.2 duplication syndrome Resources | ||
---|---|---|
|
|
Translate to: East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
Urdu,
বাংলা,
తెలుగు,
தமிழ்,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
European
español,
Deutsch,
français,
русский,
português do Brasil,
Italian,
polski
Navigation: Wellness - Encyclopedia - Health topics - Disease Index - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD
WikiMD is not a substitute for professional medical advice. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Deepika vegiraju