Coffin-Siris syndrome

Nature 
The main characteristics of Coffin-Siris syndrome are mental retardation (mild to severe), short stature, and abnormal little finger (5th digit). The cause is unknown, but believed to be inherited. Gene that carries it has not been identified yet.
Incidence 
The condition appears to affect more girls than boys although the proportion is in debate.
Type 
(G) Very specific problems