21q22.11q22.12 microdeletion syndrome

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21q22.11q22.12 microdeletion syndrome

ORPHA:261323Malformation syndrome

Also called Del(21)(q22.11q22.12) · Monosomy 21q22.11q22.12

What it is

A rare, genetic, chromosomal anomaly syndrome resulting from a partial deletion of the long arm of chromosome 21 characterized by pre- and post-natal growth delay, short stature, intellectual disability, developmental delay with severe language impairment, thrombocytopenia, and craniofacial dysmorphism which may include microcephaly, downslanted palpebral fissures, low-set ears, broad nose, thin upper vermillion, and downturned corners of the mouth. Brain MRI abnormalities (such as agenesis of the corpus callosum), behavioral problems and seizures may be associated.

Key facts

Prevalence
<1 / 1 000 000
Age of onset
Infancy, Neonatal
Inheritance
Not applicable
Classified as
Malformation syndrome

Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.

Signs and symptoms

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.

Gene

KIF15Disease-causing germline mutation(s) (loss of function)

ICD-10 codes

Q93.5filed under a broader ICD-10 category — shared with 122 other rare diseases

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

MONDO 0016845OMIM 619980OMIM 619981UMLS C5192593

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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