Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Smith-Magenis syndrome

Other Names for this Disease
  • Chromosome 17p11.2 deletion syndrome
  • SMS
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.


Newline Maker

What causes Smith-Magenis syndrome?

Most people with Smith-Magenis syndrome have a deletion of genetic material from a specific region of chromosome 17.[1][2] Although this region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, is responsible for most of the characteristic features of this condition. The loss of other genes in the deleted region may explain why there is variability in features among affected individuals.[1] A small percentage of people with Smith-Magenis syndrome have just a mutation in the RAI1 gene (not a deletion of the larger part of the chromosome).[1][2] Although these individuals have many of the major features of the condition, they are less likely than people with a chromosomal deletion to have short stature, hearing loss, and heart or kidney abnormalities.[1]
Last updated: 2/15/2012

  1. Smith-Magenis syndrome. Genetics Home Reference (GHR). 2007; Accessed 2/15/2012.
  2. Smith ACM et al.. Smith-Magenis Syndrome - Genetic Counseling. GeneReviews. January 7, 2010; Accessed 2/15/2012.