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Start free with Eleplan9q31.1q31.3 microdeletion syndrome
ORPHA:401923Malformation syndrome
Also called Del(9)(q31.1q31.3) · Monosomy 9q31.1q31.3
What it is
9q31.1q31.3 microdeletion syndrome is a rare, genetic, syndromic intellectual disability characterized by mild intellectual disability, short stature with high body mass index, short neck with cervical gibbus and dysmorphic facial features. A metabolic syndrome, including type 2 diabetes, hypercholesterolemia and hypertension has also been reported.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Neonatal
- Inheritance
- Unknown
- 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
Common30–79%
22- Abnormal facial shape
- Aortic regurgitation
- Bicuspid aortic valve
- Broad chin
- Broad nasal tip
- Cervical kyphosis
- Dilated cardiomyopathy
- Flat face
- Highly arched eyebrow
- Hypercholesterolemia
- Intellectual disability, mild
- Mandibular prognathia
- Mild global developmental delay
- Overweight
- Renovascular hypertension
- Short clavicles
- Short neck
- Short stature
- Small hand
- Tapered finger
- Thick hair
- Type II diabetes mellitus
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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