Smith-Magenis Syndrome (SMS)

Smith-Magenis Syndrome (SMS) is characterized by facial dysmorphism, behavioral problems, sleep disturbances, growth retardation and moderate mental retardation. Brachycephaly, mid-facial hypoplasia with broad flat midface, broad nasal bridge, and prognathism are classical facial features. Cognitive, psychomotor, and speech delays are common. Neurobehavioral features become more pronounced with age and can include hyperactivity, temper tantrums, attention-seeking, self-hugging, self-injurious behaviors, and sleep disturbances. About 40% of patients with the 17p11.2 deletion have structural or functional congenital heart defects. Hoarse voice, hearing loss, and eye abnormalities are frequently present as well. Hypercholesterolemia has been reported in 70% of affected patients.

Tests Available

Forms and Documents

Test Details

RAI1
  • Confirmation of clinical diagnosis
  • Recurrence risk estimation
  • Capillary Sequencing
  • Exon Array CGH

Ordering

2511
3 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)|Buccal Swabs

Billing

81405x1, 81479x1
No
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Nakamine, A. et al., Duplication of 17(p11.2p11.2) in a male child with autism and severe language delay. Am J Med Genet. 146A(5):636-643, 2008
  2. Dr. Sarah Elsea, personal communication, 2005
  3. Girirajan, S. et al., RAI1 variations in Smith-Magenis syndrome patients without 17p11.2 deletions. J Med Genet. 42: 820-28, 2005
  4. Bi, W. et al., Mutations of RAI1, a PHD-containing protein, in non-deletion patients with Smith-Magenis syndrome. Hum Genet. 115: 515-24, 2004
  5. Slager, R.et al., Mutations in RAI1 associated with Smith-Magenis syndrome. Nat Genet. 33: 466-68 2003
  6. Girirajan, S. et al., Genotype-phenotype correlation in Smith-Magenis syndrome: Evidence that multiple genes in 17p11.2 contribute to the clinical spectrum. Genet Med. 8: 417-27, 2006

Forms and Documents

Test Details

  • Suspected common microdeletion/duplication syndrome
  • Confirmation of certain karyotypes with terminal rearrangements
  • Mosaicism for a genomic imbalance (FISH)
  • FISH

Ordering

336
2-3 weeks
2-5 mL Blood - Green Top Tube

Billing

88230x1, 88271x2, 88273x1, 88291x1
No
Yes
* For price inquiries please email zebras@genedx.com