Detection of changes in global genome methylation using the cytosine-extension assay

Methylation is a reversible covalent chemical modification of DNA intended to regulate gene expression, genome stability, and chromatin structure. Although there are various methods of methylation analysis, most of them are either laborious or expensive, or both. Here, we describe a quick, inexpensive method for analysis of global genome methylation using a cytosine extension assay. The assay can be used for analysis of the total level of CpG, CNpG, and asymmetrical methylation in a given cell culture or in a plant tissue sample.