- Williams-Beuren, 7q11.23, Red
- D7Z1, 7p11.1-q11.1, Green
The Williams-Beuren probe, labelled in red, consists of three non-overlapping clones (148kb, 144kb and 204kb), which cover much of the deletion region. The probe mix also contains a control probe for the 7 centromere (D7Z1), labelled in green.
Williams-Beuren Syndrome (WBS) is a rare neurodevelopmental disorder caused by a deletion (approximately 1.5-1.8Mb in size, containing around 28 genes) within chromosome band 7q11.231. The incidence of this syndrome is estimated at 1 in 7,500 to 20,000 live births2,3,4.
Patients display a distinctive ‘elfin’ facial appearance, connective tissue problems, supravalvular aortic stenosis (SVAS), growth retardation, renal anomalies, transient hypercalcaemia, hyperacusis and mental retardation5. Haploinsufficiency of the elastin (ELN) gene has been identified as being responsible for the SVAS6,7 but none of the other clinical features of the syndrome have been unequivocally attributed to specific genes within the WBS deleted region. These genotype-phenpotype correlations are made more difficult in WBS patients as the deletion has also been shown to have an effect on normal copy number genes that neighbour the deletion breakpoints8.
In our hands, Cytocell FISH probes, have proven to be of the highest quality with bright, easy to interpret signals, thus providing confidence in our results. Cytocell’s customer support is outstanding, as their staff are extremely knowledgeable and truly care about their customers and their customers’ needs. Jennie Thurston, Director of Cytogenetics at Carolinas Pathology Group
1. Francke U et al., Hum Mol Genet 1999;8:1947-54
2. Stromme et al., J. Child. Neurol 2002;17:269-71
3. OMIM ♯194050. www.omim.org/194050
4. Schubert C. Cell Mol Life Sci 2009; 66(7):1178-97
5. Pober BR, Dykens EM, Child Adolesc Psychiatr Clin North Am 1996;5:929-43
6. Ewart et al., Nat Genet 1993; 5(1):11-16
7. Tassabehji M et al., Hum Mol Genet 1997;6:1029-36
8. Merla et al., Am J Hum Genet 2006; 79:332-341
This product is intended to be used on Carnoy’s solution (3:1 methanol/acetic acid) fixed peripheral blood samples.