Low-fidelity DNA polymerases

Also known as.... Translesion synthesis polymerases. There are two of them in Escherichia coli, polymerases IV and V, and five in human cells, polymerases ζ, η, ι, κ and Rev1 (so a knowledge of the Greek alphabet is essential when discussing them). Except for polymerase ζ, they fall into a new DNA polymerase family, designated the Y-family. Depending on the lesion, polymerase and context, they either insert the correct or an incorrect nucleotide opposite a damaged base. In the latter instances, they are responsible for generating mutations.