Overview:

DNA Polymerase Theta is a low fidelity family A DNA Polymerase that facilitates base excision repair of oxidative base damage (1). It can efficiently bypass apurinic/apyrimidinic sites and Tg lesions for when DNA replication fork encounters an unrepaired lesion, and lack of DNA Polymerase Theta activity could cause replication fork collapse or breakage (2). DNA Polymerase Theta contains extra amino acids – Inserts 1, 2 and 3 – that are not found in other family A polymerases. Inserts 1 and 2 appear to stabilize misalignments between the primer and template during base excision repair (3,4). It promotes CAG/CTG repeat expansions apparent in Huntington’s disease and other neurodegenerative disorders (3).

Gene Aliases:

PRO0327

Genbank Number:

NM_199420

References:

1. Yoshimura, M., et al. Vertebrate PolQ and PolB Cooperate in Base Excision Repair of Oxidative DNA Damage. Moll Cell. 2006, 24(1): 115-125. 2. Seki, M. et al. High-efficiency bypass of DNA damage by human DNA polymerase Q. EMBO J. 2004, 23(22):4484-4494, 3. Chan, K, Y. et al. DNA Polymerase θ promotes CAG/CTG repeat expansions in Huntington’s disease via insertion sequences of its catalytic domain. J Biol Chem. 2021, 297(4): 101144. 4. Arana, M. E., et al. Low-fidelity DNA synthesis by human DNA polymerase theta. Nucleic Acids Res. 2008, 36(11): 3847-3856.