Coffin-Lowry Syndrome

Coffin-Lowry syndrome is a rare genetic disorder characterized by craniofacial (head and facial) and skeletal abnormalities, mental retardation, short stature, and hypotonia.

The disorder affects males and females in equal numbers, but symptoms are usually more severe in males. The disorder is caused by a defective gene, RSK2, which is found on the X chromosome. Thus, the syndrome is typically more severe in males because males have only one X chromosome, while females have two. It is unclear how mutations in the DNA structure of the gene lead to the clinical findings.

Characteristic facial features may include:

  • An underdeveloped upper jaw bone (maxillary hypoplasia)
  • A broad nose
  • Protruding nostrils (nares)
  • An abnormally prominent brow
  • Down-slanting eyelid folds (palpebral fissures)
  • Widely spaced eyes (hypertelorism)
  • Large low-set ears
  • Unusually thick eyebrows

Skeletal abnormalities may include:

  • Abnormal front-to-back and side-to-side curvature of the spine (kyphoscoliosis)
  • Unusual prominence of the breastbone (pigeon chest, or pectus carinatum)
  • Dental abnormalities
  • Short, hyperextensible, tapered fingers

Other features may include feeding and respiratory problems, developmental delay, mental retardation, hearing impairment, awkward gait, stimulus-induced drop episodes, and heart and kidney involvement.

The prognosis for individuals with Coffin-Lowry syndrome varies depending on the severity of symptoms. Early intervention may improve the outlook for patients. Life span is reduced in some individuals with Coffin-Lowry syndrome.

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.