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Start free with EleplanMosaic trisomy 3 syndrome
ORPHA:100071Malformation syndrome
Also called Mosaic trisomy chromosome 3 · Trisomy 3 mosaicism
What it is
Mosaic trisomy 3 is a rare chromosomal anomaly syndrome with high phenotypic variability ranging from a mild phenotype presenting joint pain and laxity, mild facial dysmorphism (e.g. long facies, prominent eyes, dysplastic ears, downturned corners of the mouth, micrognathia) and no developmental delays to more severe phenotypes including short stature, intellectual disability, severe developmental delays, additional craniofacial dysmorphic features (e.g. brachycephaly, high forehead, flat midface, short neck) and hearing impairment, as well as skeletal (e.g. pectus excavatum, scoliosis), ocular (e.g. coloboma) and cardiac abnormalities.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Antenatal, Neonatal
- 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
Sometimes5–29%
19- Abnormal heart morphology
- Arthralgia
- Cleft palate
- Coloboma
- Failure to thrive in infancy
- Glaucoma
- Hearing impairment
- Hip dislocation
and 11 more in this range
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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