What is Smith Magenis syndrome?
Smith Magenis syndrome (SMS) is a genetic disorder that affects many parts of a person’s body. It is caused by missing information in a gene called RAI1. The main symptoms of Smith Magenis syndrome are:
- Developmental delay (especially in speech and language)
- Intellectual disabilities
- Problems with sleep
- Behavior problems
- Unique facial features
Their faces are often square shaped with a large jaw. The middle of the face is flat. Sleep problems usually begin during childhood and include problems falling asleep at night and being very tired during the day. Behavior problems can include severe temper tantrums, aggression, anxiety, difficulty paying attention, and difficulty learning. Injuring themselves is common in children with SMS. A unique symptom that is not seen in many other genetic disorders is called "lick and flip". This means that individuals lick their fingers and turn the pages of magazines or books over and over again. Other symptoms may include short height, vision problems,hearing problems, and occasionally heart and kidney problems. The type of doctor that usually diagnoses SMS is a medical geneticist. They can help coordinate care. To find a genetics clinic near you, visit the Genetic Services Search Engine on the American College of Medical Genetics website.
Smith ACM, Boyd KE, Elsea SH, et al. Smith-Magenis Syndrome. 2001 Oct 22 [Updated 2012 Jun 28]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016.