Prenatal diagnosis of partial trisomy 4q26-qter and monosomy for the Wolf-Hirschhorn critical region in a fetus with split hand malformation

We describe the results of prenatal analyses and postnatal findings in a ma le fetus with a partial trisomy for the long arm and a small terminal monos omy for the short arm of chromosome 4 with the following karyotype: 46,XY,a dd(4)(p16.3).ish dup(4)(q26qter)(wcp4+,D4S2336x3,AFMb280xa5x2,4ptel-,WHCR-) . G-banding did not identify the origin of the additional chromosomal segme nt, but this was achieved prenatally by application of RxFISH and whole chr omosome painting probes. Subsequent FISH analysis with region-specific YAC clones was used to relate the phenotypic findings such as bilateral split h and formation, specific cardiac and kidney anomalies, microtia, and hypopla stic thorax more exactly to the partial trisomy of the segment 4q26-qter. C opyright (C) 2000 John Wiley & Sons, Ltd.