Williams-Beuren syndrome: a clinical study of 55 Brazilian patients and the diagnostic use of MLPA

• Grant number: 15/50022-6
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Duration: April 01, 2015 - September 30, 2015
• Field of knowledge: Health Sciences - Medicine - Maternal and Child Health
• Principal Investigator: Chong Ae Kim
• Grantee: Chong Ae Kim
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Williams-Beuren syndrome (WBS) is a genetic disease caused by a microdeletion in the 7q11.23 region. It is characterized by congenital heart disease, mainly supravalvular aortic stenosis, mental retardation, mild short stature, facial dysmorphisms and variable abnormalities in different systems. To report the clinical findings of 55 Brazilian patients confirmed by Multiplex Ligation-dependent Probe Amplification (MLPA). Patients were followed up for 4 years at the Genetics Unit of the Instituto da Criança of the Hospital das Clínicas - FMUSP - Brazil. A kit specific for WBS was used to detect the 7q11.23 microdeletion. Two patients with negative FISH results had positive MLPA® results for WBS. The characteristics of the patients with were as follows typical WBS facies (98.2%), neuropsychomotor delay (98.2%), hyperacusis behavior (94.5%), hyperacusis (94, 5%) and congenital heart disease (81.8%). MLPA was effective in detecting the microdeletion in the 7q11.23 region to confirm the diagnosis of WBS. MLPA was also able to confirm the diagnosis of WBS in two patients with typical clinical characteristics but negative FISH results. Thus, MLPA is a promising method in the diagnostic investigation of WBS. WBS is a multi-system disorder and therefore requires multidisciplinary care and specific follow-up to prevent complications. (AU)