Synonym(s): DNA nucleotidyltransferase (DNA-directed) <p>DNA-directed DNA polymerases(<db_xref db="EC" dbkey="2.7.7.7"/>) are the key enzymes catalysing the accurate replication of DNA. They require either a small RNA molecule or a protein as a primer for the <i>de novo</i> synthesis of a DNA chain. A number of polymerases belong to this family [<cite idref="PUB00004955"/>, <cite idref="PUB00004393"/>, <cite idref="PUB00004443"/>].</p>