Dnmt1 methylates cytosine residues in hemimethylated DNA at 5’…CG…3′. Mammalian Dnmt1 is believed to be involved in carcinogenesis, embryonic development and several other biological functions . The b4k of the methylation takes place during DNA replication in the S-phase of the cell cycle.
View Human DNA (cytosine-5) Methyltransferase on New England Biolabs’s website- Human DNA (cytosine-5) Methyltransferase