Mapping of a putative tumor suppressor locus to proximal 7p in Wilms tumors.

Different findings suggest that alterations of chromosome 7 genes play a role in the development of Wilms tumors. To define the positions of these genes, we have accomplished a combined cytogenetic and molecular study on 11 sporadic Wilms tumors. In one case, where both chromosomes 7 were rearranged, the karyotypic picture was consistent with the presence of a tumor suppressor gene at 7p15. To test this hypothesis, a loss of heterozygosity analysis was performed using microsatellite markers. This revealed a common region of allele losses mapped to the proximal short arm of chromosome 7 and defined the position of the gene(s) involved in Wilms tumors within an interval of approximately 25 cM.