SNP detection. Human genomic DNA samples, with SNP in the exon 5 of p53 gene, were digested with RsaI and HindIII and subjected to direct marking using labeled probing oligonucleotides (40-bp complimentary bases) and a splint oligonucleotide (17 bp). (A) A diagrammatic representation of the SNP site in the exon 5 of p53 gene and probing oligonucleotides used. (B) SNP detection for sample A homozygous for the SNP site (C/G). (Lanes 1–4) Probes 12, 13, 14, and 15 were used, respectively. (C) SNP detection for sample B homozygous for the SNP site (G/C). (Lanes 1–4) Probes 12, 13, 14, and 15 were used, respectively. (D) SNP detection for sample C heterozygous for the SNP site (C/G, G/C). (Lanes 1–4) Probes 12, 13, 14, and 15 were used, respectively. (B–D, top) Autoradiographic pattern; (bottom) ethidium bromide-staining pattern. Nucleotide numbers (nt. numbers) are those registered in GenBank (accession no. X54156). The signals are indicated by arrows. For details, see Methods.
