DNA (cytosine-5-)-methyltransferase 1 has a role in the establishment and regulation of tissue-specific patterns of methylated cytosine residues. Aberrant methylation patterns are associated with certain human tumors and developmental abnormalities. DNMT1 mediates transcriptional repression by direct binding to HDAC2. DNMT1 in association with DNMT3B and via the
recruitment of CTCFL/BORIS, also involved in activation of BAG1 gene expression by modulating dimethylation of promoter histone H3 at H3K4 and H3K9.