Coffin-Lowry Syndrome

What is Coffin-Lowry syndrome?

Coffin-Lowry syndrome is a condition associated with mental retardation and delayed development, short stature, and skeletal abnormalities. Distinctive facial features (including wide-spaced and downward-slanting eyes, a short nose with a wide tip, and full lips) and soft hands with short, tapered fingers are also characteristic of this condition. Males are usually more severely affected than females, but the signs and symptoms of Coffin-Lowry syndrome range from very mild to severe in affected women.

How common is Coffin-Lowry syndrome?

The incidence of this condition is uncertain, but the disorder probably affects 1 in 40,000 to 50,000 births.

What genes are related to Coffin-Lowry syndrome?

Mutations in the RPS6KA3 gene cause Coffin-Lowry syndrome.

The RPS6KA3 gene makes a protein that is involved in 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 gene 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.

How do people inherit Coffin-Lowry syndrome?

This condition is inherited in an X-linked dominant pattern. A condition is considered X-linked if the mutated 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 in each cell is sufficient to cause the condition. In most cases, males (who have one X chromosome in each cell) experience more severe signs and symptoms of the disorder than females (who have two X chromosomes in each cell). A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

Most people with Coffin-Lowry syndrome have no history of the condition in their families. These cases are caused by new mutations in the RPS6KA3 gene.

What other names do people use for Coffin-Lowry syndrome?

• CLS
• Mental retardation with osteocartilaginous abnormalities