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Start free with EleplanMYT1L-related developmental delay-intellectual disability-obesity syndrome
ORPHA:647799Disease
Also called MYT1L-associated neurodevelopmental disorder
What it is
A rare neurodevelopmental syndrome characterized by global developmental delay, intellectual disability of varying severity or learning difficulties (e.g. dysphasia, dyspraxia, dyscalculia, dysgraphia) and behavioral disorders (stereotypies, autism spectrum disorder, impulsiveness or intolerance to frustration, self or hetero aggression). Additional clinical features include weight disorders (overweight/obesity) and eating behaviour disorders (including hyperphagia, tachyphagia, obsessive food compulsions), non-specific magnetic resonance imaging (brain MRI) abnormalities, ophthalmologic abnormalities, epilepsy, sleep disorders and non-specific dysmorphism. Endocrine abnormalities are rarely associated.
Key facts
- Inheritance
- Autosomal dominant
- Classified as
- Disease
Signs and symptoms
Very common80–99%
5Common30–79%
19- Abnormal eating behavior
- Abnormality of coordination
- Abnormal repetitive mannerisms
- Aggressive behavior
- Almond-shaped palpebral fissure
- Attention deficit hyperactivity disorder
- Bulbous nose
- Deeply set eye
- Exaggerated cupid's bow
- Fatigue
- Floppy infant
- Full cheeks
- Impulsivity
- Intellectual disability, moderate
- Motor delay
- Obesity
- Polyphagia
- Sleep abnormality
- Specific learning disability
Sometimes5–29%
29- Abnormal temper tantrums
- Anxiety
- Astigmatism
- Bruxism
- Congenital muscular torticollis
- Cryptorchidism
- Decreased fetal movement
- Failure to thrive
and 21 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.
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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