The genomic basis of the Williams-Beuren syndrome

Cell Mol Life Sci. 2009 Apr;66(7):1178-97. doi: 10.1007/s00018-008-8401-y.


The Williams-Beuren syndrome is a genomic disorder (prevalence: 1/7,500 to 1/20,000), caused by a hemizygous contiguous gene deletion on chromosome 7q11.23. Typical symptoms comprise supravalvular aortic stenosis, mental retardation, overfriendliness and visuospatial impairment. The common deletion sizes range of 1.5-1.8 mega base pairs (Mb), encompassing app. 28 genes. For a few genes, a genotype-phenotype correlation has been established. The best-explored gene within this region is the elastin gene; its haploinsufficiency causes arterial stenosis. The region of the Williams-Beuren syndrome consists of a single copy gene region (approximately 1.2 Mb) flanked by repetitive sequences--Low Copy Repeats (LCR). The deletions arise as a consequence of misalignment of these repetitive sequences during meiosis and a following unequal crossing over due to high similarity of LCRs. This review presents an overview of the Williams-Beuren syndrome region considering the genomic assembly, chromosomal rearrangements and their mechanisms (i.e. deletions, duplications, inversions) and evolutionary and historical aspects.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Chromosome Aberrations
  • Chromosomes, Human, Pair 7 / genetics
  • Gene Deletion
  • Gene Dosage
  • Genome, Human*
  • Humans
  • Williams Syndrome / genetics*