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Start free with EleplanBardet-Biedl syndrome
ORPHA:110Disease
Also called BBS
What it is
A rare genetic multisystem disorder characterized by the variable association of retinal dystrophy, obesity, polydactyly, genitourinary and kidney anomalies, learning disability and hypogonadism, with a wide spectrum of other minor manifestations.
Key facts
- Prevalence
- 1-9 / 100 000 (Specific population)
- Age of onset
- Antenatal, Childhood, Infancy, Neonatal
- Inheritance
- Autosomal recessive, Oligogenic
- Classified as
- Disease
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%
4- Childhood-onset truncal obesityDiagnostic criterion
- Cone/cone-rod dystrophyDiagnostic criterion
- Neurodevelopmental delayDiagnostic criterion
- Obesity
Common30–79%
31- Abnormal electroretinogram
- Abnormality of the genitourinary systemDiagnostic criterion
- Abnormality of the sense of smellDiagnostic criterion
- Abnormal oral cavity morphologyDiagnostic criterion
- Atypical behaviorDiagnostic criterion
- Autism
- Blindness
- Brachydactyly
- Chronic kidney diseaseDiagnostic criterion
- Cognitive impairmentDiagnostic criterion
- Color vision defect
- Decreased HDL cholesterol concentration
- Dental crowding
- Depression
- Elevated circulating hepatic transaminase concentration
- High palate
- Hypertension
- Hypertriglyceridemia
- Hypodontia
- HypogonadismDiagnostic criterion
- Hypoplasia of penis
- Hypoplasia of the ovary
- Impaired fasting glucose
- Nyctalopia
- Nystagmus
- Photophobia
- Postaxial polydactylyDiagnostic criterion
- Reduced visual acuity
- Short attention span
- Short stature
- Specific learning disabilityDiagnostic criterion
Sometimes5–29%
54- Abnormal heart morphologyDiagnostic criterion
- Abnormality of speech or vocalization
- Abnormality of the endocrine systemDiagnostic criterion
- Abnormality of the gastrointestinal tractDiagnostic criterion
- Anxiety
- Aplasia/Hypoplasia of the vagina
- Asthma
- Astigmatism
and 46 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.
Genes
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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