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Start free with EleplanMosaic trisomy 4 syndrome
ORPHA:96059Malformation syndrome
Also called Mosaic trisomy chromosome 4 · Trisomy 4 mosaicism
What it is
Mosaic Trisomy 4 is a rare autosomal anomaly, due to the presence of an extra copy of chromosome 4 in a fraction of all cells, with a variable phenotype characterized by intrauterine growth retardation, low birth weight/length/OFC, mild intellectual deficit, congenital heart defects, hypertrophic cardiomyopathy, dysmorphic features (asymmetry of the face, eyebrow anomalies, low-set, posteriorally rotated, dysplastic ears, micro-/retrognathia), characteristic thumb abnormalities (aplasia, hypoplasia) and skin abnormalities (hypo/hyperpigmentation). Delayed puberty may be associated.
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.
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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