Splicing of exon 5 in the WT1 gene is disrupted in Wilms' tumour

Using a reverse transcriptase polymerase chain reaction to examine alternate splicing at site I (exon 5) and site II (exon 9) in the Wilms' tumour suppressor gene, WT1, we found that in seven of the 10 Wilms' tumours examined, splicing at site I was disrupted. This is predicted to result in isoform imbalance in Wilms' tumours, with an increase in isoforms in which the 17 amino acids encoded by exon 5 are missing. These observations could not be explained by mutations or rearrangements in flanking introns. Disrupted alternate splicing of exon 5 may play a role in the aetiology of Wilms' tumour.