Synonym(s): - Hypothyroidism - dysmorphism - postaxial polydactyly - intellectual deficit - SBBYSS - Say-Barber-Biesecker-Young-Simpson syndrome
Classification (Orphanet): - Rare developmental defect during embryogenesis - Rare endocrine disease - Rare genetic disease - Rare neurologic disease Entire classification		Classification (ICD10): (no data available)
Epidemiological data: Class of prevalence: <1 / 1 000 000 Average age onset: neonatal/infancy Average age of death: - Type of inheritance: autosomal dominant		External references: 1 OMIM reference - See No MeSH references
More Info - Orphanet

Gene symbol	UniProt reference	OMIM reference
KAT6B	Q8WYB5	605880

- Blepharophimosis / short palpebral fissures
- Hypothyroidy
- Hypotonia
- Intellectual deficit / mental / psychomotor retardation / learning disability
- Long / large / bulbous nose
- Low set ears / posteriorly rotated ears
- Micrognathia / retrognathia / micrognathism / retrognathism
- Prominent occiput / occipital bossing
- Short stature / dwarfism / nanism
- Sloping forehead
- Undescended / ectopic testes / cryptorchidia / unfixed testes

- Antihelix anomaly
- Atrial septal defect / interauricular communication
- Atrioventricular canal
- Branchial / posterior auricular / preauricular / cheek cysts / fistulae
- Camptodactyly of some fingers
- Cleft palate without cleft lip / submucosal cleft palate / bifid uvula
- Clinodactyly of fifth finger
- Ectopic / agenesis / dysgenesis / hypoplastic thyroid
- Failure to thrive / difficulties for feeding in infancy / growth delay
- Hyperextensible joints / articular hyperlaxity
- Insterstitial / subtelomeric microdeletion / deletion
- Microcephaly
- Patent ductus arteriosus
- Polyhydramnios
- Repeat respiratory infections
- Seizures / epilepsy / absences / spasms / status epilepticus
- Simian crease / transverse / unique palmar crease
- Ventricular septal defect / interventricular communication

- Defect / anomaly of lacrimal system
- Oral cavity / tongue neoplasm / tumor / carcinoma / cancer