A boy with classical Rubinstein-Taybi syndrome but no detectable mutation in the CREBBP and EP300 genes.

Rubinstein-Taybi syndrome (RTS) is a rare autosomal dominant genetic disorder and is characterized by mental retardation, distinctive facial features, broad and often angulated thumbs and great toes. We report on a 7 year old boy with classical Rubinstein-Taybi syndrome. His facial and clinical features were very typical, including broad thumbs with radial angulation and broad great toes.