INTERSTITIAL INSERTION OF Y-SPECIFIC DNA-SEQUENCES INCLUDING SRY INTOCHROMOSOME-4 IN A 45,X MALE CHILD

A 45,X chromosome complement was found in the lymphocytes and skin fib roblast cultures of a male infant with minor facial anomalies and gast rointestinal abnormalities, Fluorescence in situ hybridization (FISH) studies with DNA probes specific for the entire Y chromosome (painting ) and SRY identified insertion of a short piece of Y chromosome DNA, i ncluding the SRY region, into a der(4) chromosome at 4p15. FISH studie s with DNA probes specific for Wolf-Hirschhorn syndrome (WHS) and telo mere of 4p indicated that these 2 regions were intact and that the ins ertion of Y DNA had occurred proximal to the WHS region, High-resoluti on chromosome analysis performed after FISH studies showed an altered banding pattern of 4p at the region of insertion, The typical Giemsa d ark band of 4p15 was consistently replaced by a gray band; this probab ly indicates deletion of the distal part of 4p15, The consequences of the double-chromosome anomaly in this patient were discussed in relati on to his phenotype. (C) 1997 Wiley-Liss, Inc.