What is (are) Holt-Oram syndrome ?
Holt-Oram syndrome is a genetic condition characterized by skeletal abnormalities of the hands and arms (upper limbs) and heart problems. Affected people have at least one bone abnormality in the wrist, many of which can be detected only by X-ray. Additional skeletal abnormalities may also be present. About 75% of affected people have heart problems, including congenital heart defects and/or cardiac conduction disease (an abnormality in the electrical system that coordinates contractions of the heart chambers). Holt-Oram syndrome is caused by mutations in the TBX5 gene and is inherited in an autosomal dominant manner. Most cases result from new mutations in the gene and occur in people with no family history of the condition.