What is DNA methylation?

DNA methylation refers to the covalent bonding of a methyl group at the 5 'carbon position of the cytosine of the CpG dinucleotide in the genome under the action of DNA methylation transferase. It can cause changes in chromatin structure, DNA conformation, DNA stability, and the interaction between DNA and protein. It can control gene expression and change genetic performance without changing the DNA sequence. DNA methylation enzymes are divided into 2 categories, namely maintaining DNA methyltransferase (Dnmtl or maintaining methylase) and de novo methylase