Mysterious and fascinating: DNA polymerase É© remains enigmatic 20 years after its discovery.

With the publication of the first paper describing the biochemical properties of DNA polymerase iota (polɩ), the question immediately arose as to why cells harbor such a low-fidelity enzyme which often violates the Watson-Crick base pairing rules? Yet 20 years after its discovery, the cellular function of polɩ remains unknown. Here, we provide a graphical review of the unique biochemical properties of polɩ and speculate about the cellular pathways in which enigmatic polɩ may participate.