[Application of molecular genetics in microdeletion syndromes: report of the results of 21 FISH tests for Williams Beuren syndrome 3rd part of microdeletion project]

Twenty one FISH tests for confirmation of Williams Beuren Syndrome [19 Peripheral blood, and two amniotic cells cultures] have been performed. FISH tests in four couples with one affected child of Williams Syndrome are negative for abnormal critical segment of del [7p11-23], which indicates that the deletion in the affected children is of de novo origin. There are two negative FISH tests out of 8 candidates suspected for WS. One is positive for Prader-Willi Syndrome, the other one is negative for WS, so far. One negative FISH test out of 8 indicates the importance of FISH test in detection of microdeletion disease, especially in Williams Beuren Syndrome