Behavioral features of Williams Beuren syndrome compared to Fragile X syndrome and subjects with intellectual disability without defined etiology

Williams-Beuren syndrome (WBS) is a genetically determined neurodevelopmental disorder caused by a heterozygous deletion of 26-28 genes on chromosome band 7q11.23. During the past few years, researchers and clinicians have significantly contributed to define the phenotype of the syndrome, including its cognitive and behavioral aspects. However, it is not well known yet whether the psychological problems are specific to the syndrome or secondary to the intellectual disability (ID). The aim of our study was to better define the psychopathological profile of WBS and whether or not it is related with IQ or anxiety symptoms. Twenty-five subjects (12 girls, 13 boys) with a diagnosis of WBS were compared to 27 boys with Fragile X Syndrome and to 24 boys with ID of non-specific etiology using the Child Behavior Checklist. Anxiety, depression and attention problems were the main behavioral problems found in WBS with no gender differences. Significant differences between cohorts were observed in somatic complaints, delinquent behavior, aggressive behavior, and externalizing problems. Some associations between IQ and anxiety items were found. The findings are discussed in terms of behavioral phenotypes, genetic implications and ID. © 2010 Elsevier Ltd.