What is DNA methyltransferase?
'''DNA methyltransferase''' (DNA MTase, DNMT) is a ''family'' of [[enzymes]], They [[catalyze]] the transfer of a [[methyl]] group to [[DNA]]. [[DNA methylation]] has many biological functions. == Mammals == Three active DNA methyltransferases have been identified in mammals. They are named [[DNMT1]],<ref>{{cite web | title = DNMT1 | work = Gene Symbol Report | publisher = [[HUGO Gene Nomenclature Committee]] | url = https://www.genenames.org/data/hgnc_data.php?hgnc_id=2976 | access-date = 2012-09-27 | archive-date = 2012-10-06 | archive-url = https://web.archive.org/web/20121006100223/http://www.genenames.org/data/hgnc_data.php?hgnc_id=2976 | url-status = dead }}</ref> [[DNMT3a]],<ref>{{cite web | title = DNMT3A | work = Gene Symbol Report | publisher = [[HUGO Gene Nomenclature Committee]] | url = https://www.genenames.org/data/hgnc_data.php?hgnc_id=2978 | access-date = 2012-09-27 | archive-date = 2012-10-02 | archive-url = https://web.archive.org/web/20121002035438/http://www.genenames.org/data/hgnc_data.php?hgnc_id=2978 | url-status = dead }}</ref> and [[DNMT3b]].<ref>{{cite web | title = DNMT3B | work = Gene Symbol Report | publisher = [[HUGO Gene Nomenclature Committee]] | url = https://www.genenames.org/data/hgnc_data.php?hgnc_id=2979 | access-date = 2012-09-27 | archive-date = 2012-11-20 | archive-url = https://web.archive.org/web/20121120210447/http://www.genenames.org/data/hgnc_data.php?hgnc_id=2979 | url-status = dead }}</ref> Recently, a fourth enzyme DNMT3c has been discovered specifically expressed in the male germline in the mouse.<ref>{{cite journal | vauthors = Barau J, Teissandier A, Zamudio N, Roy S, Nalesso V, Hérault Y, Guillou F, Bourc'his D | s2cid = 30907442 | display-authors = 6 | title = The DNA methyltransferase DNMT3C protects male germ cells from transposon activity | journal = Science | volume = 354 | issue = 6314 | pages = 909–912 | date = November 2016 | pmid = 27856912 | doi = 10.1126/science.aah5143 | bibcode = 2016Sci...354..909B }}</ref> What these enzymes do is make [[DNA