[Familial supravalvular aortic stenosis. Investigation in a family and review of the literature].

Familial supravalvular aortic stenosis is a rare autosomal dominant condition. It may be distinguished from the Williams-Beuren syndrome by the absence of the characteristic dysmorphic appearances and of mental retardation. The case of a 9-year-old girl with a severe surgical stenosis led to the diagnosis of the same malformation in the mother and two brothers. This family adds to the 121 cases reported in the literature describing the main features of SVAS. Molecular biological advances have shown that familial SVAS and the Williams syndrome are due to mutation of the elastin gene located at 7q11-23. In the Williams syndrome the allele of this gene is completely absent and there is also probably deletion of contiguous genes, which explains involvement of cognitive function. In SVAS, the genetic lesion, mutation or microdeletion is more limited, explaining the usually isolated aortic malformation. Other studies are necessary to confirm these results.