Wilms tumor(WT) is one of the most common renal malignancies in children.Although several genetic loci such as the WT1,WT2,p53 and ?-catenin genes have been considered to be associated with WT,the causes of the tumor are still unknown.Recently the US researchers have identified a new tumor suppressor gene that is mutated in WT.The biological function of the protein encoded by WTX is yet unknown,however,the gene's location in the X chromosome is of particular interest.This review highlights the current study of the gene mutated in Wilms tumor.