POPULATION VARIATION AT THE POLYMORPHIC APALI RESTRICTION ENZYME SITEIN INTRON-5 OF THE WT1 GENE

We examined 63 unrelated individuals from the United States for the Ap a-LI polymorphism in intron 5 of the WT1 gene. Allele frequencies of 0 .13 and 0.87 for the A and B alleles, respectively, and a heterozygosi ty index of 24% contrast sharply with previous data obtained in the Ja panese population where allele frequencies of 0.55 and 0.45 for the A and B alleles and a heterozygosity index of 59% were reported, These d ata suggest genetic heterogeneity at the WT1 locus, which may contribu te to the differences in the incidence of Wilms tumor between the two population groups.