Enables DNA-directed DNA polymerase activity. Involved in several processes, including cellular response to glucose stimulus; response to gamma radiation; and response to hyperoxia. Located in mitochondrion and terminal bouton. Part of gamma DNA polymerase complex. Used to study Alpers-Huttenlocher syndrome and hepatocellular carcinoma. Biomarker of status epilepticus. Human ortholog(s) of this gene implicated in several diseases, including mitochondrial DNA depletion syndrome (multiple); mitochondrial myopathy (multiple); neurodegenerative disease (multiple); ovarian disease (multiple); and sensory ataxic neuropathy, dysarthria, and ophthalmoparesis. Orthologous to human POLG (DNA polymerase gamma, catalytic subunit). [provided by Alliance of Genome Resources, Apr 2022]