Melting Curve Assays for DNA Methylation Analysis

The ability of sodium bisulfite to modify cytosines in a methylation-dependent manner allows the conservation of DNA methylation information during PCR amplification. PCR products amplified from bisulfite-modified DNA have significantly different base compositions according to whether they originate from methylated or unmethylated variants of the target template. Different base compositions give rise to different thermal properties of the PCR products. Hence, melting analysis of amplification products in methylation studies allows the determination of whether the PCR products originate from methylated or unmethylated templates. Here, we briefly review recent advances in methodologies based on melting analyses of PCR products derived from bisulfite-modified templates and provide a methodology for methylation-sensitive high-resolution melting.