LOCALIZATION OF A NOVEL T(1-7) TRANSLOCATION ASSOCIATED WITH WILMS-TUMOR PREDISPOSITION AND SKELETAL ABNORMALITIES

Cytogenetic analysis of predisposition syndromes has played a critical role in the elucidation of the genetics of Wilms' tumor (WT). Therefo re, we became interested in a patient who presented with a WT and a ne phrogenic rest in the contralateral kidney (suggestive of a predisposi tion) and a de novo t(1;7)(q42;p15) constitutional translocation as th e only visible cytogenetic abnormality. He also had bilateral radial a plasia and other skeletal abnormalities, but there was no manifestatio n of any syndrome previously associated with WT. In the tumor, the tra nslocation was retained, and the other 7p region was lost by the forma tion of an isochromosome i(7q). Here, we report the localization of th e chromosome 7 breakpoint within a yeast artificial chromosome (YAC) c ontig by using fluorescence in situ hybridization (FISH), localizing t he breakpoint between markers sWSS355 and sWSS1449. A number of YACs s pan the breakpoint and, thus, contain the region that is disrupted by the translocation. This may represent the site of a novel tumor suppre ssor gene that is involved in WT and also in normal renal development. (C) 1996 Wiley-Liss, Inc.