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Start free with Eleplan20q11.2 microduplication syndrome
ORPHA:363659Malformation syndrome
Also called Dup(20)(q11.2)
What it is
20q11.2 microduplication syndrome is a rare chromosomal anomaly syndrome, due to partial duplication of the long arm of chromosome 20, characterized by psychomotor and developmental delay, moderate intellectual disability, metopic ridging/trigonocephaly, short hands and/or feet and distinctive facial features (epicanthus, hypoplastic supraorbital ridges, horizontal/downslanting palpebral fissures, small nose with depressed nasal bridge and anteverted nostrils, prominent cheeks, retrognathia and small, thick ears). Growth delay and cryptororchidism are often associated features.
Key facts
- Age of onset
- Infancy, Neonatal
- Classified as
- Malformation syndrome
Signs and symptoms
Common30–79%
28- Bifid scrotum
- Coarse facial features
- Cryptorchidism
- Delayed speech and language development
- Depressed nasal bridge
- Epicanthus
- Flat face
- Full cheeks
- Gingival overgrowth
- Global developmental delay
- Growth delay
- High myopia
- Intellectual disability, moderate
- Microcephaly
- Microtia
- Palpebral edema
- Periorbital edema
- Posteriorly rotated ears
- Prominent metopic ridge
- Proptosis
- Retrognathia
- Short foot
- Short nose
- Short palm
- Tented philtrum
- Tented upper lip vermilion
- Underdeveloped supraorbital ridges
- Wide nasal bridge
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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