The current review showed which the WT1 gene was alternatively spliced at Ex4a to make isoforms with opposing roles in apoptosis, anti-apoptotic isoforms (important WT1 isoforms) and pro-apoptotic isoform (truncated Ex4a(+)WT1 isoform). Several other genes associated in apoptosis, these as p53 [39], Survivin [40], Fas [41], and caspase-9 [42] are acknowledged to provide isoforms with opposing role