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ORPHA:10Malformation syndrome
What it is
A rare sex chromosome number anomaly disorder characterized, genetically, by the presence of an extra X and Y chromosome in males and, clinically, by tall stature, dysfunctional testes associated with infertility and insufficient testosterone production, cognitive, affective and social functioning impairments, global developmental delay, and an increased risk of congenital malformations.
Key facts
- Prevalence
- 1-9 / 100 000 (at birth, Europe)
- Age of onset
- Adolescent, Childhood, Infancy, Neonatal
- Inheritance
- Not applicable, 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
Very common80–99%
7Common30–79%
31- Abnormality of dental enamel
- Abnormality of the shoulder
- Anxiety
- Asthma
- Attention deficit hyperactivity disorder
- Blepharophimosis
- Carious teeth
- Chronic otitis media
- Clinodactyly of the 5th finger
- Constipation
- Delayed eruption of teeth
- Depression
- Elbow dislocation
- Epicanthus
- Feeding difficulties in infancy
- Flat occiput
- Gynecomastia
- Hypertelorism
- Hypotonia
- Joint hypermobility
- Obesity
- Open bite
- Pes planus
- Radioulnar synostosis
- Recurrent respiratory infections
- Strabismus
- Tall stature
- Taurodontia
- Thick lower lip vermilion
- Tremor
- Upslanted palpebral fissure
Sometimes5–29%
23- Abnormal cardiovascular system morphology
- Abnormal repetitive mannerisms
- Apnea
- Ataxia
- Autism
- Broad jaw
- Cleft palate
- Cryptorchidism
and 15 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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