What is Coffin-Lowry syndrome?
Coffin-Lowry syndrome is a condition that affects many parts of the body. The signs and symptoms are usually more severe in males than in females, although the features of this disorder range from very mild to severe in affected women.
Males with Coffin-Lowry syndrome typically have severe to profound mental retardation and delayed development. Affected women may be intellectually normal, or they may have mental retardation ranging from mild to profound. Beginning in childhood or adolescence, some people with this condition experience brief episodes of collapse when excited or startled by a loud noise. These attacks are called stimulus-induced drop episodes (SIDEs).
Most affected males and some affected females have distinctive facial features including a prominent forehead, widely spaced and downward-slanting eyes, a short nose with a wide tip, and a wide mouth with full lips. These features become more pronounced with age. Soft hands with short, tapered fingers are also characteristic of Coffin-Lowry syndrome. Additional features of this condition include short stature, an unusually small head (microcephaly), progressive abnormal curvature of the spine (kyphoscoliosis), and other skeletal abnormalities.
How common is Coffin-Lowry syndrome?
The incidence of this condition is uncertain, but researchers estimate that the disorder affects 1 in 40,000 to 50,000 people.
Mutations in the RPS6KA gene cause Coffin-Lowry syndrome.
The RPS6KA3 gene provides instructions for making a protein that is involved in signaling within cells. Researchers believe that this protein helps control the activity of other genes and plays an important role in the brain. The protein is involved in cell signaling pathways that are required for learning, the formation of long-term memories, and the survival of nerve cells. Gene mutations result in the production of little or no RPS6KA3 protein, but it is unclear how a lack of this protein causes 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 of the condition is unknown.
Read more about the RPS6KA3 gene.
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.
Between 70 percent and 80 percent of 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. The remaining 20 percent to 30 percent of affected individuals have other family members with Coffin-Lowry syndrome.
Where can I find information about treatment for Coffin-Lowry syndrome?
These resources address the management of Coffin-Lowry syndrome and may include treatment providers.
Where can I find additional information about Coffin-Lowry syndrome?
You may find the following resources about Coffin-Lowry syndrome helpful. These materials are written for the general public.
- MedlinePlus - Health information (3 links)
- Additional NIH Resources - National Institutes of HealthNational Institute of Neurological Disorders and Stroke
- Educational resources - Information pages (2 links)
- Patient support - For patients and families (3 links)
You may also be interested in these resources, which are designed for healthcare professionals and researchers.
- Gene Reviews - Clinical summary
- Gene Tests - DNA tests ordered by healthcare professionals
- PubMed - Recent literature
- OMIM - Genetic disorder catalog
What other names do people use for Coffin-Lowry syndrome?
- Mental retardation with osteocartilaginous abnormalities
See How are genetic conditions and genes named? in the Handbook.
What if I still have specific questions about Coffin-Lowry syndrome?
- See How can I find a genetics professional in my area? in the Handbook.
- Ask the Genetic and Rare Diseases Information Center.
- Submit your question to Ask the Geneticist.
Where can I find general information about genetic conditions?
The Handbook provides basic information about genetics in clear language.
- What does it mean if a disorder seems to run in my family?
- What are the different ways in which a genetic condition can be inherited?
- If a genetic disorder runs in my family, what are the chances that my children will have the condition?
- Why are some genetic conditions more common in particular ethnic groups?
These links provide additional genetics resources that may be useful.