Prevalence estimation of Williams syndrome.

Department of Paediatrics, Rikshospitalet, The National Hospital, Oslo, Norway.
Journal of Child Neurology (Impact Factor: 1.67). 05/2002; 17(4):269-71. DOI: 10.1177/088307380201700406
Source: PubMed

ABSTRACT There are limited population-based data on the occurrence of Williams syndrome. We estimated its prevalence combining data from two investigations. One was an epidemiologic study originally designed to assess the prevalence and etiology of mental retardation among 30,037 Norwegian children born between 1980 and 1985 and living in Akershus County on January 1, 1993. The other investigation was a national survey of Williams syndrome. In the first study, 213 children were referred for evaluation, whereas the second study comprised 57 cases with Williams syndrome born between 1970 and 1992, who were referred for evaluation from all Norwegian counties. The epidemiologic study revealed three children with Williams syndrome, whereas one additional case complying with our demographic criteria was identified in the national survey, thus giving a prevalence of 1 in 7500. In all cases, a typical chromosome 7q11.23 deletion was detected. We also conclude that Williams syndrome is not an uncommon cause of mental retardation, with a prevalence of approximately 6% of patients with genetic etiology.

1 Follower
  • [Show abstract] [Hide abstract]
    ABSTRACT: Les syndromes microdélétionnels sont définis par la présence d’une anomalie chromosomique de taille mineure (inférieure à 5 mégabases) ou aneusomie segmentaire, décelable par cytogénétique moléculaire (FISH : Fluorescent in Situ Hybridization). Les syndromes microdélétionnels représentent des syndromes cliniques avec des phénotypes suffisamment caractéristiques pour être reconnus cliniquement. Actuellement la FISH est la technique de choix pour rechercher ces syndromes. Plusieurs syndromes microdélétionnels peuvent être confirmés aisément, les plus recherchés sont Le syndrome de Williams (microdélétion en 7q11.23) et le syndrome de la délétion 22q11 (microdélétion en 22q11.2). Le syndrome de Williams est caractérisé par une anomalie du développement qui associe un retard psycho-moteur, une dysmorphie du visage évocatrice et un profil cognitif et comportemental spécifique, une sténose aortique supravalvulaire -SASV- le plus souvent. Le Syndrome de la délétion 22q11 se caractérise par l’association de plusieurs malformations d’expression variable: une cardiopathie congénitale de type conotroncal, une dysmorphie faciale discrète mais caractéristique et une hypoplasie du thymus et des parathyroïdes. Nous rapportons nos premières observations au CHU Hassan II confirmées par FISH : Syndrome de la délétion 22q11 (n:2) et un syndrome de Williams. Le but de cet article est la mise à jour de nos connaissances sur ces deux syndromes et la mise en valeur du rôle de la cytogénétique moléculaire dans le diagnostic et le conseil génétique des syndromes microdélétionnels.
    01/2012; 11.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Research on behavioral phenotypes in neurogenetic syndromes has primarily focused on aspects of the affected child's behavior. However, the impact of having a child with a neurogenetic syndrome on aspects of family functioning can be significant and differ across syndromes. Parents (N = 381) of school-aged children with one of four neurogenetic syndromes: fragile X Syndrome (FXS), Prader Willi Syndrome (PWS), Williams Syndrome (WS) and 22q11.2 (22qDEL) were asked about challenges, restrictions, future concerns and positive aspects arising from having an affected child. Factors associated with these aspects were analysed via logistic regression. Restrictions were most often reported by parents of children with FXS. The factors significantly (p < .01) associated with the parent reported restrictions were the presence of a behavioral/psychiatric condition and a lower level of receptive communication. The challenges endorsed most often were the child's learning and social skills difficulties. Significant differences (p < .01) between the syndromes were noted for many of the challenges. Ninety-six percent of parents endorsed at least one positive aspect but most aspects endorsed did not differ between the genetic syndromes. Having a behavioral/psychiatric condition was the only factor significantly associated (p < .01) with endorsing a lower number of positive aspects and a higher number of challenges. There are some commonalities but also significant differences across syndromes regarding views on how a child's syndrome affects family functioning. These differences may be important with regard to how to counsel and support affected families. The presence of behavioral/psychiatric conditions is an important predictor of negative family outcome across the syndromes.
    Journal of Genetic Counseling 01/2015; DOI:10.1007/s10897-015-9820-1 · 1.75 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Williams syndrome (WS) is a genetic disorder caused by a heterozygous contiguous gene deletion on chromosome 7q11.23. Clinical features of the disease include low IQ and deficit in some cog-nitive domains, and the presence of relatively strong abilities in social drive, face processing, language , and musical skills. The presence of a strong predisposition to the development of musical-ity in individuals affected by WS leads us to suppose that some genes deleted in this syndrome are somehow involved in the evolution of this ability, and that these genes could act in normal conditions as " suppressors of music ability ". To test this hypothesis, we carried out an " in silico " analysis by using the Ingenuity Pathway Analysis (IPA) software to identify the interaction between genes mapped in the WS critical region and genes previously related to musical ability by literature data. This approach allowed us to identify 3 networks of interaction, involving AVPR1A, NCF1, UNC5C and LAT2 in the first network, STX1A and SLC6A4 in the second one and only WS related genes in the last one. Among these associations, the one involving STX1A and SLC6A4 suggested a possible mechanism of interaction was based on the influence played by STX1A deletion on the serotonin levels through a decrease of SLC6A4 activity.
    Open Journal of Genetics 03/2015; 5(1):12-26. DOI:10.4236/ojgen.2015.51002