DAP-kinase methylation-specific PCR. (A) A completely methylated sample was diluted 1:2 to 1:100 into an unmethylated DNA and the “methylated” PCR reaction is shown. A distinct band was visible up to a dilution of 1:16 (6.75% positive). Co is the negative control and MW is the 100-bp molecular weight marker. (B) MSP for unmethylated and methylated DAP-kinase for 3 patients (patient a: lanes 1-2; patient b: lanes 3-4; and patient c: lanes 5-6). Adistinct band for the unmethylated reaction is visible at 106 bp for all patients, whereas only the DNAof patient c is methylated (98-bp band). Lanes 7 and 8 are negative controls for unmethylated and methylated DAP-kinase.