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ORPHA:819Malformation syndrome
Also called 17p11.2 microdeletion syndrome
What it is
A rare, genetic, neurodevelopmental disorder characterized by cognitive impairment of variable severity, behavioral abnormalities, and sleep disturbance. Patients present with distinctive physical features and a wide range of malformations (e.g. cardiac, renal).
Key facts
- Prevalence
- 1-9 / 100 000 (Europe)
- Age of onset
- Adolescent, Adult, Childhood, Infancy, Neonatal
- Inheritance
- Autosomal dominant
- 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%
31- Abnormality of speech or vocalization
- Abnormality of the dentition
- Abnormal pineal melatonin secretionPathognomonic sign
- Abnormal repetitive mannerisms
- Abnormal tracheobronchial morphology
- Anxiety
- Attention deficit hyperactivity disorder
- Brachycephaly
- Brachydactyly
- Broad forehead
- Deeply set eye
- Delayed eruption of primary teeth
- Delayed speech and language development
- Depressed nasal bridge
- Frontal bossing
- Global developmental delay
- Hoarse voice
- Hyporeflexia
- Hypotonia
- Intellectual disability
- Large face
- Midface retrusion
- Obesity
- Recurrent otitis media
- Self-injurious behavior
- Sleep abnormality
- Synophrys
- Taurodontia
- Tented upper lip vermilion
- Upslanted palpebral fissure
- Wide nasal bridge
Common30–79%
46- Abnormal cardiovascular system morphology
- Abnormal heart morphology
- Abnormal temper tantrums
- Anteverted nares
- Aplasia/Hypoplasia of the corpus callosum
- Broad palm
- Clinodactyly of the 5th finger
- Coarse facial features
- Cognitive impairment
- Conductive hearing impairment
- Constipation
- Decreased fetal movement
- EEG abnormality
- Failure to thrive in infancy
- Feeding difficulties in infancy
- Gait disturbance
- Gastroesophageal reflux
- Hyperacusis
- Hypercholesterolemia
- Hypertelorism
- Hypertriglyceridemia
- Impaired pain sensation
- Impulsivity
- Mandibular prognathia
- Microcornea
- Micrognathia
- Myopia
- Onychotillomania
- Open mouth
- Peripheral neuropathy
- Pes planus
- Polyembolokoilamania
- Recurrent upper respiratory tract infections
- Scoliosis
- Short nose
- Short philtrum
- Short rem sleep
- Short stature
- Sleep-wake cycle disturbance
- Square face
- Strabismus
- Tip-toe gait
- Toe syndactyly
- Velopharyngeal insufficiency
- Ventriculomegaly
- Vocal cord polyp
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.
Gene
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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