Methylation status of p16 gene in colorectal carcinoma and normal colonic mucosa

Figure 1 PCR-based detection of 5’ CpG island methylation. N: normal colonic mucosa; T: colorectal carcinoma. A 5’ CpG island sequence (340 bp) of the p16 gene was PCR amplified after sufficient digestion with a methylation sensitive enzyme Hpa-II (2), Sac-II (3) and Sma-I (5) and undige sted control (1, 4). A: case 715c, in the normal colonic mucosa, Hpa-II and Sma-I sites unmethylation (N2, N5) and Sac-II sites partial methylation (N3); in the colorectal carcinoma, Hpa-II and Sac-II site partial methylati on (T2, T3) and Sma-I site unmethylation (T5). B: case 701, in the normal co lonic mucosa, Sac-II site full methylation (N3) and Sma-I and Hpa-II sites partial methylation (N5, N2); in the colorectal carcinoma, Hpa-II, Sac-II and Sma-I sites full methylation (T2, T3, T5).