Supravalvular aortic stenosis and peripheral pulmonary stenosis in family with balanced translocation t(7;14) and break point within the elastin gene region

Abstract

We present a family form of balanced translocation t(7;14) found in a mother and her two sons. The mother had an aortic cardiac murmur, without hemo-dynamic repercussions and the children had almost identical clinical findings, significant supravalvular aortic stenosis, left ventricle intracavitary stenosis and multiple peripheral pulmonary stenosis but with no other clinical manifestations of Williams-Beuren syndrome, except, perhaps, a deep, metallic voice. The conventional chromosome analysis unexpectedly revealed a balanced translocation between chromosomes 7 and 14, the same translocation was found in the mother and both children. Subsequent fluorescent in situ hybridization analysis with WSCR probe showed that the break point was within the elastin gene region in the mother and both children. The proband karyotype was interpreted, according to ISCN (2005) as 46,XY,t(7;14) (q11.23;p12).ish t(7;14)(D7Z1+,ELNsp;D14Z1/D22Z1+,ELNsp+)mat, in other words, translocation had disrupted the elastin region and may have contributed to the developmental defects in Williams-Beuren syndrome. When going through the references on genetic examination of supravalvular aortic stenosis, Williams-Beuren syndrome and some other conditions that could not be placed in any of these two terminal categories because of the various phenotype characteristics, we found that such a result has not yet been published.