The establishment of a cell identification method more accurate than the conventional morphological and cell-type-specific marker analyses has been desired. DNA methylation is related to the gene activity including gene-silencing and is a key mechanism of epigenetics underling cellular differentiaion and development in mammals. Recent studies indicated that there exist unique genomic DNA methylation profiles specific to the cell type. DNA methylation profiles a mechanism for memorizing the set of genes inherent in individual type of cells. In this chapter, we present the methods to analyze DNA methylation status for identifying cells or tissues.
