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Start free with EleplanHao-Fountain syndrome due to 16p13.2 microdeletion
ORPHA:500055Etiological subtype
Also called Chromosome 16p13.2 deletion syndrome · Del(16)(p13.2) · Monosomy 16p13.2
What it is
A partial deletion of the short arm of chromosome 16 characterized by developmental delay, intellectual disability, speech delay, autism spectrum disorder, epilepsy, hypogonadism, and hypotonia. The behavioral profile includes impulsivity, compulsivity, stubbornness, manipulative behaviors, temper tantrums, and aggressive behaviors.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Childhood, Infancy
- Inheritance
- Not applicable
- Classified as
- Etiological subtype
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%
4Common30–79%
19- Aggressive behavior
- Asthma
- Attention deficit hyperactivity disorder
- Autistic behavior
- Cerebral white matter atrophy
- Chronic constipation
- Dilated third ventricle
- Esotropia
- Failure to thrive
- Feeding difficulties in infancy
- Gait disturbance
- Gastroesophageal reflux
- Hypogonadism
- Hypoplasia of the corpus callosum
- Hypotonia
- Intellectual disability
- Neonatal hypotonia
- Seizure
- Short stature
Sometimes5–29%
30- Abnormal temper tantrums
- Absent speech
- Brachycephaly
- Chronic diarrhea
- Cryptorchidism
- Decreased fetal movement
- Flexion contracture
- Hearing impairment
and 22 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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