The endogenous background level of oxidant-induced DNA damage in vivo has been assayed by measuring 8-hydroxydeoxyguanosine (oh8dG), thymine and thymidine glycol in urine and oh8dG in DNA. The level of oxidative DNA damage as measured by oh8dG in normal rat liver is shown to be extensive (1/130 000 bases in nuclear DNA and 1/8000 bases in mitochondrial DNA), especially in mtDNA. The methylatio adduct 7-methylguanine (m7G) has also been found. m7G is one of about 5 adducts found on methylating DNA, and oh8dG is one of about 20 adducts found on oxidizing DNA, e.g., by radiation. We also discuss 3 hitherto unrecognized antioxidants in man. © 1989.
Ames, B. N. (1989). Endogenous DNA damage as related to cancer and aging. Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 214(1), 41–46. https://doi.org/10.1016/0027-5107(89)90196-6