A CRITICAL MUTATION IN BOTH WT1 ALLELES IS NOT SUFFICIENT TO CAUSE WILMS-TUMOR

The WT1 gene is a tumor suppresser gene for Wilms' tumor (WT). Inactiv ation of both alleles has been proposed as the cause of WT. We encount ered a patient with Denys-Drash syndrome associated with WT whose WT1 gene had a homozygous point mutation not only in WT but also in renal tissue adjacent to the WT and in the germline. These findings indicate that factor(s) other than the loss of WT1 are required for WT to deve lop.