Williams Syndrome

Abstract

Abstract Williams syndrome (WS) is a complex condition involving multiple organ systems, unique personality characteristics, distinctive facial features, elastin arteriopathy, cognitive impairment (usually mild mental retardation), connective tissue abnormalities, and endocrine growth abnormalities. Over 99% of individuals with a clinical diagnosis of WS have a 1.6 Mb deletion of chromosome 7q11.23 that contains the 20 contiguous genes of the critical region for WS that encompasses the elastin (ELN) gene. The prevalence of WS in Norway was reported to be 1 in 7500 births. In 1961 Williams et al. described four young children in New Zealand with peculiar facies, supravalvular aortic stenosis (SVAS), and mental retardation. A year later, Beuren et al.6 reported three German patients with the same findings and questioned whether the association of SVAS, mental retardation, and facial characteristics constituted a syndrome. The following year Black and Bonham Carter7 noted that the facies of children with SVAS described by Williams and coworkers and those with idiopathic hypercalcemia described by Fanconi were quite similar and suggested that they had different manifestations of the same condition. In 1964, Garcia et al. demonstrated that the two conditions were the same when they published a case report describing SVAS and developmental delay in an individual who had a history of hypercalcemia. The syndrome was infantile hypercalcemia, SVAS, WS, or Williams-Beuren sundrome.” Jones and Smith pointed out in 1975,8 however, that not all children with WS have SVAS and hypercalcemia.