Coffin-Siris syndrome, first described in 1970, is a rare genetic abnormality.
Coffin-Siris syndrome should not be confused with Coffin-Lowry syndrome.
It occurs more frequently in females (with a M:F of ~4:1).
One of the most typical features is absence or hypoplasia of the nails of the fifth fingers, thus the alternative name of “fifth digit syndrome”.
Most frequent findings include:
- intellectual disability
- coarse features
- hypoplasia or absence of the fifth distal phalanges and finger-nails
- feeding difficulties
- muscular hypotonia (floppy baby)
- Dandy-Walker malformation
- agenesis of the corpus callosum
- there is an association with medulloblastoma
It is thought most likely to relate to a gene on chromosome 7, however, its exact location has yet to be determined.