Autosomal dominant
This form is caused by a change in one copy of the FGF9 gene, which encodes a growth factor important for skeletal development. Studied variants impair the protein's ability to pair up and bind its receptor, and they can be inherited from an affected parent or arise de novo.
Signs and symptoms
Fused joints, commonly at the elbow and between bones in the hands, wrists, ankles and fingers, limiting movement. Fusion of the neck (cervical) spine can also occur.
What a diagnosis changes
Orthopaedic and hand assessment, with physiotherapy and occupational therapy to support function. Each child of an affected person has a 1 in 2 chance of inheriting the change, so genetic counselling and family testing can be offered.
Also known as
deafness-Hermann type symphalangism syndrome; facio-audio-symphalangism; symphalangism-brachydactyly syndrome; WL syndrome
Includes 4 related subtypes ↓Hide subtypes ↑
- multiple synostoses syndrome 1
- multiple synostoses syndrome 2
- multiple synostoses syndrome 3
- multiple synostoses syndrome 4
