Figure 1. Detection of the p53 polymorphism and construction of haplotype

A: Locations of the polymorphic sites within the p53 gene and the nature of the polymorphisms are shown. The allelic difference resulting from codon 72 polymorphism were determined by BstU I digestion of the PCR product obtained by using a pair of primers selected from exon 3 and intron 4 of the gene. B: All possible combinations of DNA fragments resulting from BstU I digestion of the PCR products and the haplotypes determined based on the digestion pattern are shown. C: Polyacrylamide gel (6%) analysis of PCR products from five representative samples, with (+) and without (-) BstU I digestion, is shown. The haplotypes determined based on the analysis are indicated at the bottom of the panel. The ins-Arg haplotype has not been detected in any sample. Lane M is a pBS/Hae III digested molecular weight marker. The sizes of the molecular weight marker and the BstU I digest are shown in the left and the right sides of the gel, respectively. DNA bands present only in samples 4 and 5 (four right lanes) above 458 bp size marker are due to heteroduplex formation between the 448 bp and 432 bp bands, which are retained in the native polyacrylamide gel.