Williams syndrome

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Williams syndrome
Classification and external resources
ICD-10 Q93.8
ICD-9 758.9
OMIM 194050
MedlinePlus 001116
eMedicine ped/2439 
MeSH D018980

Williams syndrome (WS; also Williams-Beuren syndrome or WBS) is a rare neurodevelopmental disorder caused by a deletion of about 26 genes from the long arm of chromosome 7.[1] It is characterized by a distinctive, "elfin" facial appearance, along with a low nasal bridge; an unusually cheerful demeanor and ease with strangers; mental retardation coupled with unusual (for persons who are diagnosed as mentally retarded) language skills; a love for music; and cardiovascular problems, such as supravalvular aortic stenosis and transient hypercalcaemia. The syndrome was first identified in 1961 by Dr. J. C. P. Williams of New Zealand. [2]


[edit] Symptoms

Individuals with Williams syndrome are highly verbal and sociable (having what has been described as a "cocktail party" type personality), but lack common sense and typically have inhibited intelligence. Individuals with WS hyperfocus on the eyes of others in social engagements.[3] Phenotypically patients tend to have widely spaced teeth, a long philtrum, and flattened nasal bridge.[4]

People with Williams syndrome often have hyperacusis and phonophobia which resembles noise-induced hearing loss, but this may be due to a malfunctioning auditory nerve.[5][6] Individuals with the condition tend to demonstrate a love of music[4], and also appear significantly more likely to possess perfect pitch.[7]

There also appears to be a higher prevalence of left-handedness and left-eye dominance in those with Williams.[8] Individuals with Williams syndrome also report higher anxiety levels as well as phobia development, which may be associated with hyperacusis.[9]

[edit] Visual perception

Individuals with Williams syndrome have problems with visual processing, but this is related to difficulty in dealing with complex spatial relationships rather than to issues with depth perception.[10]

[edit] Treatment

No curative therapy is known for Williams syndrome exists with care being mostly supportive.[4] Guidelines published by the American Academy of Pediatrics include cardiology evaluations, developmental and psychoeducational assessment, and many other examination, laboratory, and anticipatory guidance recommendations.[11]

[edit] Cause

Williams Syndrome genes[12][13]
LAT2 · LIMK1 · MDH2 · NCF1
TRIM50 · TRIM73 · TRIM74

Williams syndrome is caused by the deletion of genetic material from the region q11.23 of chromosome 7. The deleted region includes more than 20 genes, and researchers believe that the loss of several of these genes probably contributes to the characteristic features of this disorder. CLIP2, ELN, GTF2I, GTF2IRD1, and LIMK1 are among the genes that are typically deleted in people with Williams syndrome. Researchers have found that loss of the ELN gene, which codes for the protein elastin, is associated with the connective-tissue abnormalities and cardiovascular disease (specifically supravalvular aortic stenosis (SVAS) and supravalvular pulmonary stenosis (SVPS)) found in many people with this syndrome. Studies suggest that deletion of LIMK1, GTF2I, GTF2IRD1, and perhaps other genes may help explain the characteristic difficulties with visual–spatial tasks. Additionally, there is evidence that the loss of several of these genes, including CLIP2, may contribute to the unique behavioral characteristics, learning disabilities, and other cognitive difficulties seen in Williams syndrome.[citation needed]

[edit] Epidemiology

Williams syndrome has an estimated prevalence of 1 in 7,500 to 1 in 20,000.[1]

[edit] In popular culture

Williams syndrome was featured in a 2007 episode of Law & Order: Special Victims Unit entitled "Savant," in which a girl with the condition is the only witness to the attack of her mother. The girl did not see the attacker but heard him speak, and her absolute pitch helped the police catch her mother's assailant.

In the Wes Anderson film The Royal Tenenbaums, the character of Dudley has fictional Heinsbergen Syndrome, which features many similarities with Williams syndrome. Dudley has difficulty understanding spatial relations (dyslexia, colorblindness, inability to solve puzzles) coupled with an acute sense of hearing.

In the season 4 episode 13, No More Mr. Nice Guy, of the television program House, Dr. House incorrectly diagnosed a patient with Williams syndrome based on a suspected genetic inability to identify suspect causes, leading to the patient's "niceness".

In the 2002 movie Fish Don't Blink, Lea Thompson's character, Clara, has Williams syndrome.

Similarities in appearance of the Alfred E. Neuman mascot in Mad magazine have been suggested.[citation needed]

Three of the cast members of MTV's new show entitled "How's Your News?" have Williams syndrome.

Williams syndrome was discussed in a segment of the Scientific American Frontiers episode Growing Up Different.

[edit] References

  1. ^ a b Martens MA, Wilson SJ, Reutens DC (2008). "Research Review: Williams syndrome: a critical review of the cognitive, behavioral, and neuroanatomical phenotype". J Child Psychol Psychiatry 49 (6): 576–608. doi:10.1111/j.1469-7610.2008.01887.x. PMID 18489677. 
  2. ^ Dobbs, David (July 8, 2007). "The Gregarious Brain.". New York Times. http://www.nytimes.com/2007/07/08/magazine/08sociability-t.html. Retrieved on 2007-09-25. "If a person suffers the small genetic accident that creates Williams syndrome, he’ll live with not only some fairly conventional cognitive deficits, like trouble with space and numbers, but also a strange set of traits that researchers call the Williams social phenotype or, less formally, the “Williams personality”: a love of company and conversation combined, often awkwardly, with a poor understanding of social dynamics and a lack of social inhibition." 
  3. ^ Riby DM, Hancock PJ (2008). "Viewing it differently: Social scene perception in Williams syndrome and Autism". Neuropsychologia 46 (11): 2855–60. doi:10.1016/j.neuropsychologia.2008.05.003. PMID 18561959. 
  4. ^ a b c http://www.mamashealth.com/syndrome/willsyn.asp
  5. ^ Gothelf D, Farber N, Raveh E, Apter A, Attias J (February 2006). "Hyperacusis in Williams syndrome: characteristics and associated neuroaudiologic abnormalities". Neurology 66 (3): 390–5. doi:10.1212/01.wnl.0000196643.35395.5f. PMID 16476938. http://www.neurology.org/cgi/pmidlookup?view=long&pmid=16476938. 
  6. ^ Johnson LB, Comeau M, Clarke KD (April 2001). "Hyperacusis in Williams syndrome". J Otolaryngol 30 (2): 90–2. doi:10.2310/7070.2001.20811. PMID 11770962. 
  7. ^ Sacks O (May 1995). "Musical ability". Science 268 (5211): 621–2. doi:10.1126/science.7732360. PMID 7732360. 
  8. ^ Van Strien JW, Lagers-Van Haselen GC, Van Hagen JM, De Coo IF, Frens MA, Van Der Geest JN (2005). "Increased prevalences of left-handedness and left-eye sighting dominance in individuals with Williams-Beuren syndrome". J Clin Exp Neuropsychol 27 (8): 967–76. doi:10.1080/13803390490919119. PMID 16207621. 
  9. ^ Blomberg S, Rosander M, Andersson G (2006). "Fears, Hyperacusis and musicality in Williams syndrome". Res Dev Disabil 27 (6): 668–80. doi:10.1016/j.ridd.2005.09.002. PMID 16269236. 
  10. ^ Van der Geest JN, Lagers-van Haselen GC, van Hagen JM, et al (October 2005). "Visual depth processing in Williams-Beuren syndrome". Exp Brain Res 166 (2): 200–9. doi:10.1007/s00221-005-2355-1. PMID 15965761. 
  11. ^ Committee on Genetics, American Academy of Pediatrics (01 May 2001). "Health care supervision for children with Williams syndrome". Pediatrics 107 (5): 1192–2004. PMID 11331709. http://aappolicy.aappublications.org/cgi/content/full/pediatrics;107/5/1192. 
  12. ^ Merla G, Howald C, Henrichsen CN, et al (August 2006). "Submicroscopic deletion in patients with Williams-Beuren syndrome influences expression levels of the nonhemizygous flanking genes". Am. J. Hum. Genet. 79 (2): 332–41. doi:10.1086/506371. PMID 16826523. 
  13. ^ Schubert C, Laccone F (November 2006). "Williams-Beuren syndrome: determination of deletion size using quantitative real-time PCR". Int. J. Mol. Med. 18 (5): 799–806. PMID 17016608. http://www.spandidos-publications.com/ijmm/article.jsp?article_id=ijmm_18_5_799. 

[edit] Further reading

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