Coffin-Lowry syndrome

Coffin-Lowry syndrome is a condition associated with mental retardation and delayed development, characteristic facial features, and skeletal abnormalities. Males are usually more severely affected than females, but the condition can range from very mild to severe in affected women. This condition is inherited in an X-linked dominant pattern. Males usually carry this disease more often than females because males only have one X chromosome, while females have two.

Mutations in the RPS6KA3 gene cause Coffin-Lowry syndrome. The RPS6KA3 gene makes a protein that is involved with signaling within cells. Researchers believe that the protein helps control the activity of other genes and may play an important role in the central nervous system. Mutations in the RPS6KA3 disturb the function of the protein, but it is not well understood how mutations lead to the signs and symptoms of Coffin-Lowry syndrome. Some people with the features of Coffin-Lowry syndrome do not have identified mutations in the RPS6KA3 gene. In these cases, the cause is unknown.

This condition is inherited in an X-linked dominant pattern. A condition is considered X-linked if the gene that causes the disorder is located on the X chromosome (one of the two sex chromosomes). The inheritance is dominant if one copy of the altered gene is sufficient to cause the condition. In most cases, males experience more severe symptoms of the disorder than females. A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

A majority of boys with Coffin-Lowry syndrome have no history of the condition in their families. These cases are caused by new mutations in the RPS6KA3 gene. A new mutation means that neither parent has the altered gene, but the affected individual could pass it on to his children.

There is no cure and no standard course of treatment for Coffin-Lowry syndrome. Treatment is symptomatic and supportive, and may include physical and speech therapy and educational services.

This article incorporates public domain text from The U.S. National Library of Medicine and the National Institute of Neurological Disorders and Stroke.