“…The Polγ holoenzyme is a heterotrimer consisting of two identical accessory subunits (Polγ-B) and one catalytic subunit (Polγ-A), where the accessory subunits enhance the processivity and catalytic function of Polγ-A (Gray and Wong, 1992;Johnson et al, 2000;Carrodeguas et al, 2002;reviewed in Kaguni, 2004). Until recently, Polγ was thought to be the sole polymerase within the mitochondrion that was responsible for both mtDNA replication and repair; however, at least four other DNA polymerases have been noted to play a role in mtDNA maintenance namely, DNA polymerase beta, PrimPol, polymerase theta, and polymerase zeta (Singh et al, 2015;Wisnovsky et al, 2016;Sykora et al, 2017;Bailey et al, 2019;reviewed in Bailey and Doherty, 2017;Kaufman and Van Houten, 2017;Krasich and Copeland, 2017). Until recently, Polγ was thought to be the sole polymerase within the mitochondrion that was responsible for both mtDNA replication and repair; however, at least four other DNA polymerases have been noted to play a role in mtDNA maintenance namely, DNA polymerase beta, PrimPol, polymerase theta, and polymerase zeta (Singh et al, 2015;Wisnovsky et al, 2016;Sykora et al, 2017;Bailey et al, 2019;reviewed in Bailey and Doherty, 2017;Kaufman and Van Houten, 2017;Krasich and Copeland, 2017).…”