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Case Report
Importance of
molecular techniques in diagnosing Williams-Beuren syndrome
Iravathy Goud.K1*,
Dayakar.S1, Babu.S.J1, VijayaLakshmi.K1,
Peter Miny2,
Friedel Wenzel3, Dharmendra Jain4,
Vimarsh Raina4
1Molecular
Biology and Cytogenetics lab, Apollo Health city, Jubilee
Hills, Banjara Hills, Hyderabad-500033
2Abteilung
Medizinische Genetik,Departement Klinisch-Biologische
Wissenschaften Universitäts-Kinderspital beider Basel (UKBB)
CH-4005.
3Chromosomenlaboratory,The
Children's Hospital, Basel,
CH-4005.
4Immunology
and Molecular Biology, Indraprastha Apollo Hospitals, Sarita
Vihar, New Delhi-110044
Corresponding author Email:
driravathy_g@apollohospitals.com . Phone Number:
+91-040-23607777, +91-09989831655
Received 06 November , 2009; Accepted 22 February, 2010
Abstract
Williams’s
syndrome is a complex syndrome characterized by
developmental abnormalities, craniofacial dysmorphic
features, and cardiac anomalies. Clinical diagnostic
criteria are available for WS; the mainstay for diagnosis is
detection of the contiguous gene deletion of the Williams-Beuren
syndrome critical region (WBSCR) that encompasses the
elastin (ELN) gene which can be detected using fluorescent
in situ hybridization (FISH) or targeted mutation analysis.A
two and half year old child was referred to our Molecular
Biology and Cytogenetic lab for cytogenetic analysis which
revealed normal male karyotype. As the diagnosis could not
be confirmed the sample was further tested for WBS critical
region- ELN-locus in 7q11 by FISH analysis. Loss of ELN-locus
in 7q11 confirmed the clinical diagnosis of WBS in the
child. The parents of the child benefited enormously by
learning that the risk of recurrence was < 1% as this
microdeletion occurs sporadically (new mutation). The main
aim of this study is to emphasize on two aspects: (i) the
importance of making use of modern molecular techniques to
diagnose such a syndrome and (2) the difficulties faced by
the physician to provide appropriate diagnosis and the
adequate genetic counseling to such patients due to the lack
of such molecular facilities.
Keywords: Williams- Beuren Syndrome, cytogenetics,
FISH.
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