Paired box genes, PAX-2 and PAX-8, are not frequently mutated in Wilms tumor.

To determine whether PAX-2 and PAX-8 are involved in Wilms tumor (WT) pathogenesis, we sought mutations in these two genes in 99 Wilms tumors of favorable histology. We screened the entire protein coding sequences as well as the intronic regions adjacent to exons, using denaturing HPLC followed by sequencing of samples displaying abnormal chromatograms. In PAX-2, a silent polymorphism was found within exon 2 and exon 8 in 1% and 21% of cases, respectively. Three apparently silent polymorphisms were also found in PAX-8, two in exon 5 (2 of 99 cases or 2%) and one in exon 6 (22 of 99 cases or 22%), all of which were located 3' to the exons. In conclusion, no evidence for disease causing mutation was found using this technique, and so the direct involvement of either of these two genes in WT is unlikely.