Microdissecting the genetic events in nephrogenic rests and wilms' tumor development

Nephrogenic rests are precursor lesions associated with about 40 % of Wilms ’ tumors. This study identi-fies genetic steps occurring in the development of Wilms ’ tumor. Thirty-four Wilms ’ tumors with neph-rogenic rests and/or areas of anaplasia were micro-dissected from paraffin sections to determine whether and at what stage loss of heterozygosity (LOH) occurred, using polymerase chain reaction-based polymorphic markers at 11p13, 11p15, and 16q. LOH at these loci have been identified in Wilms’ tumors and are associated with identified or putative tumor suppressor genes. Three cystic nephromas/ cystic partially differentiated nephroblastomas were also examined. LOH was detected in six cases at 11p13 and in six cases at 11p15, and two of these cases ha