[Clinical and genetic characteristics of Williams-Beuren syndrome: 2 cases report].

To explore the clinical and genetic characteristics of Williams-Beuren syndrome (WBS) and to raise awareness of the disease. The characteristics of clinical manifestations, personal history, cardiac ultrasound, brain magnetic resonance imaging (MRI), electroencephalogram (EEG) and chromosome detection results of two cases with WBS were analyzed. The two patients were both male and the age was 11 months and 1 day, and 9 months and 9 days, respectively. They both suffered from cardiovascular malformation: case one presented supravalvular aortic stenosis, and case two showed atrial septal defect and patent ductus arteriosus. Both of the cases were exhibited characteristic facial features of WBS, including full orbital, spherical nose, flat nasal bridge, long philtrum and thick lips. For the mental development, case one displayed moderate to severe developmental retardation, and case two showed severe developmental retardation. In addition, case one presented bilateral indirect inguinal hernia and hydrocele, and case two manifested feeding difficulties, buried penis and infantile spasms. Personal history: case one's mother had tocolytic therapy during pregnancy period, and case one was born at full-term by cesarean section due to amniotic fluid pollution. Supplementary examination: brain MRI of the two cases were no significant abnormalities; the EEG of case two showed hypsarrhythmia, and the epileptic spasms were recorded. Chromosome detection results: case one was identified as 7q11.23 deletion including the fragment deletion mutation of elastin (ELN) gene by multiplex ligation dependent probe amplification method, and case two was found with 7q11.21q11.23 deletion by high resolution G-band method. The two cases with WBS both had cardiovascular malformations, special facial features, mental retardation and connective tissue or urinary system abnormality. The supravalvular aortic stenosis of case one may be associated with the deletion of ELN gene, and the occurrence of epilepsy of case two may be related to the q11.21 deletion beyond the 7q11.23 region.