Autosomal dominant
Caused by loss of one working copy of GLI3, a transcription factor in the hedgehog signalling pathway. It can be inherited from an affected parent; the share of new (de novo) cases is not known.
Signs and symptoms
Extra digits, typically on the thumb side of the feet and the little-finger side of the hands, with webbing between fingers or toes. A large head and widely spaced eyes with a broad forehead are common. Less often there is developmental delay, intellectual disability or seizures, which are more likely with large deletions that include neighbouring genes.
What a diagnosis changes
Hand and foot surgery when needed, with head size and developmental monitoring in childhood. Children of an affected person have a 1 in 2 chance of inheriting the condition, so genetic counselling and family testing are offered.
Genes analysed
Also known as
GCPS; GLI3-related Greig cephalopolysyndactyly spectrum; Greig cephalosyndactyly syndrome; Greig syndrome; Greig's syndrome; polysyndactyly with peculiar skull shape
Includes 1 related subtype ↓Hide subtypes ↑
- Greig cephalopolysyndactyly-contiguous gene syndrome
