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Start free with Eleplan13q12.3 microdeletion syndrome
ORPHA:412035Malformation syndrome
Also called Del(13)(q12.3) · Monosomy 13q12.3
What it is
13q12.3 microdeletion syndrome is a rare chromosomal anomaly characterized by moderate intellectual disability, speech delay, postnatal microcephaly, eczema or atopic dermatitis, characteristic facial features (malar flattening, prominent nose, underdeveloped alae nasi, smooth philtrum, and thin vermillion of the upper lip), and reduced sensitivity to pain.
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%
20- Atopic dermatitis
- Camptodactyly
- Constipation
- Delayed speech and language development
- Failure to thrive
- Hyperactivity
- Hypermetropia
- Impaired pain sensation
- Intellectual disability, moderate
- Intrauterine growth retardation
- Low insertion of columella
- Malar flattening
- Oligodontia
- Recurrent respiratory infections
- Self-mutilation
- Short stature
- Thin upper lip vermilion
- Underdeveloped nasal alae
- Upper eyelid edema
- Vomiting
Sometimes5–29%
10- Allergy
- Chronic otitis media
- Congenital diaphragmatic hernia
- Cryptorchidism
- Hearing impairment
- Hemihypotrophy of lower limb
- Hip dysplasia
- Kyphoscoliosis
and 2 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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