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Start free with EleplanXq12-q13.3 duplication syndrome
ORPHA:314389Malformation syndrome
Also called Dup(X)(q12-q13.3) · Kaya-Prontera syndrome
What it is
Xq12-q13.3 duplication syndrome is a rare chromosomal anomaly syndrome, resulting from the partial duplication of the long arm of chromosome X, characterized by global developmental delay, autistic behavior, microcephaly and facial dysmorphism (including down-slanting palpebral fissures, depressed nasal bridge, anteverted nares, long philtrum, down-slanting corners of the mouth). Seizures have also been reported in some patients.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy, Neonatal
- Inheritance
- X-linked recessive
- 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
Very common80–99%
35- 2-3 toe syndactyly
- Abnormal basal ganglia MRI signal intensity
- Abnormality of visual evoked potentials
- Agitation
- Anterior creases of earlobe
- Atypical behavior
- Autistic behavior
- Bulimia
- Cleft earlobe
- Cryptorchidism
- Cutaneous finger syndactyly
- Decreased circulating alkaline phosphatase activity
- Decreased serum insulin-like growth factor 1
- Delayed speech and language development
- Depressed nasal bridge
- Eczematoid dermatitis
- Elevated circulating creatine kinase concentration
- Epicanthus
- Everted lower lip vermilion
- Generalized amyotrophy
- Global developmental delay
- Hypertelorism
- Hypoplasia of the corpus callosum
- Hypotonia
- Hypsarrhythmia
- Impaired pain sensation
- Intellectual disability
- Microcephaly
- Moderate global developmental delay
- Numerous nevi
- Optic disc pallor
- Pectus excavatum
- Short stature
- Triangular face
- Ventriculomegaly
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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