WILMS-TUMOR GENETICS

Wilms tumor (WT), a sporadic and familial childhood kidney tumor, is g enetically heterogeneous. One WT gene, WT1 at 11p13, has been cloned, but only a minority of WTs carry detectable mutations at that locus. W T1 can also be excluded as the predisposition gene in most WT families , implying the existence of other WT genes. Studies of WT families hav e demonstrated that familial predisposition is also heterogeneous and involves at least two other loci besides WT1, In addition to WT1 and t he familial predisposition genes, a role for other genes in the develo pment of WTs is implied by the somatic occurrence of genetic and epige netic alterations such as loss of heterozygosity and loss of imprintin g in tumors and, rarely, the observation of nonchromosome-11 constitut ional aberrations in WT patients. Determining the pattern of presence or absence of these various genetic alterations in tumors and elucidat ing the function of the genes involved will provide a better understan ding of the cellular processes that are critical for normal cell growt h and differentiation, but are abrogated in the course of tumorigenesi s, (C) 1998 Wiley-Liss, Inc.